Search Results

Search found 62532 results on 2502 pages for 'id string'.

Page 431/2502 | < Previous Page | 427 428 429 430 431 432 433 434 435 436 437 438  | Next Page >

  • what "Debug Assertion Failed" mean and how to fix it, c++?

    - by nonon
    hi, why this program gives me a "Debug Assertion Failed" Error Message while running #include "stdafx.h" #include "iostream" #include "fstream" #include "string" using namespace std; int conv_ch(char b) { int f; f=b; b=b+0; switch(b) { case 48: f=0; break; case 49: f=1; break; case 50: f=2; break; case 51: f=3; break; case 52: f=4; break; case 53: f=5; break; case 54: f=6; break; case 55: f=7; break; case 56: f=8; break; case 57: f=9; break; default: f=0; } return f; } class Student { public: string id; size_t id_len; string first_name; size_t first_len; string last_name; size_t last_len; string phone; size_t phone_len; string grade; size_t grade_len; void print(); void clean(); }; void Student::clean() { id.erase (id.begin()+6, id.end()); first_name.erase (first_name.begin()+15, first_name.end()); last_name.erase (last_name.begin()+15, last_name.end()); phone.erase (phone.begin()+10, phone.end()); grade.erase (grade.begin()+2, grade.end()); } void Student::print() { int i; for(i=0;i<6;i++) { cout<<id[i]; } cout<<endl; for(i=0;i<15;i++) { cout<<first_name[i]; } cout<<endl; for(i=0;i<15;i++) { cout<<last_name[i]; } cout<<endl; for(i=0;i<10;i++) { cout<<phone[i]; } cout<<endl; for(i=0;i<2;i++) { cout<<grade[i]; } cout<<endl; } int main() { Student k[80]; char data[1200]; int length,i,recn=0; int rec_length; int counter = 0; fstream myfile; char x1,x2; char y1,y2; char zz; int ad=0; int ser,j; myfile.open ("example.txt",ios::in); int right; int left; int middle; string key; while(!myfile.eof()){ myfile.get(data,1200); char * pch; pch = strtok (data, "#"); printf ("%s\n", pch); j=0; for(i=0;i<6;i++) { k[recn].id[i]=data[j]; j++; } for(i=0;i<15;i++) { k[recn].first_name[i]=data[j]; j++; } for(i=0;i<15;i++) { k[recn].last_name[i]=data[j]; j++; } for(i=0;i<10;i++) { k[recn].phone[i]=data[j]; j++; } for(i=0;i<2;i++) { k[recn].grade[i]=data[j]; j++; } recn++; j=0; } //cout<<recn; string temp1; size_t temp2; int temp3; for(i=0;i<recn-1;i++) { for(j=0;j<recn-1;j++) { if(k[i].id.compare(k[j].id)<0) { temp1 = k[i].first_name; k[i].first_name = k[j].first_name; k[j].first_name = temp1; temp2 = k[i].first_len; k[i].first_len = k[j].first_len; k[j].first_len = temp2; temp1 = k[i].last_name; k[i].last_name = k[j].last_name; k[j].last_name = temp1; temp2 = k[i].last_len; k[i].last_len = k[j].last_len; k[j].last_len = temp2; temp1 = k[i].grade; k[i].grade = k[j].grade; k[j].grade = temp1; temp2 = k[i].grade_len; k[i].grade_len = k[j].grade_len; k[j].grade_len = temp2; temp1 = k[i].id; k[i].id = k[j].id; k[j].id = temp1; temp2 = k[i].id_len; k[i].id_len = k[j].id_len; k[j].id_len = temp2; temp1 = k[i].phone; k[i].phone = k[j].phone; k[j].phone = temp1; temp2 = k[i].phone_len; k[i].phone_len = k[j].phone_len; k[j].phone_len = temp2; } } } for(i=0;i<recn-1;i++) { k[i].clean(); } char z; string id_sear; cout<<"Enter 1 to display , 2 to search , 3 to exit:"; cin>>z; while(1){ switch(z) { case '1': for(i=0;i<recn-1;i++) { k[i].print(); } break; case '2': cin>>key; right=0; left=recn-2; while(right<=left) { middle=((right+left)/2); if(key.compare(k[middle].id)==0){ cout<<"Founded"<<endl; k[middle].print(); break; } else if(key.compare(k[middle].id)<0) { left=middle-1; } else { right=middle+1; } } break; case '3': exit(0); break; } cout<<"Enter 1 to display , 2 to search , 3 to exit:"; cin>>z; } return 0; } the program reads from a file example.txt 313121crewwe matt 0114323111A # 433444cristinaee john 0113344325A+# 324311matte richee 3040554032B # the idea is to read fixed size field structure with a text seprator record strucutre

    Read the article

  • Android App Crashes On Second Run

    - by user1091286
    My app runs fine on first run. On the Menu I added two choices options and quit. options which set up a new intent who goes to a PreferenceActivity and quit which simply call: "android.os.Process.killProcess(android.os.Process.myPid());" On the second time I run my app (after I quit from inside the emulator) it crashes.. Ideas? the menu is called by the foolowing code: @Override public boolean onCreateOptionsMenu(Menu menu) { getMenuInflater().inflate(R.menu.menu , menu); return true; } - @Override public boolean onOptionsItemSelected(MenuItem item) { // Set up a new intent between the updater service and the main screen Intent options = new Intent(this, OptionsScreenActivity.class); // Switch case on the options switch (item.getItemId()) { case R.id.options: startActivity(options); return true; case R.id.quit: android.os.Process.killProcess(android.os.Process.myPid()); return true; default: return false; } Code for SeekBarPreference: package com.testapp.logic; import com.testapp.R; import android.content.Context; import android.content.res.TypedArray; import android.preference.Preference; import android.util.AttributeSet; import android.util.Log; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.view.ViewParent; import android.widget.RelativeLayout; import android.widget.SeekBar; import android.widget.SeekBar.OnSeekBarChangeListener; import android.widget.TextView; public class SeekBarPreference extends Preference implements OnSeekBarChangeListener { private final String TAG = getClass().getName(); private static final String ANDROIDNS="http://schemas.android.com/apk/res/android"; private static final String PREFS="com.testapp.logic"; private static final int DEFAULT_VALUE = 5; private int mMaxValue = 100; private int mMinValue = 1; private int mInterval = 1; private int mCurrentValue; private String mUnitsLeft = ""; private String mUnitsRight = ""; private SeekBar mSeekBar; private TextView mStatusText; public SeekBarPreference(Context context, AttributeSet attrs) { super(context, attrs); initPreference(context, attrs); } public SeekBarPreference(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); initPreference(context, attrs); } private void initPreference(Context context, AttributeSet attrs) { setValuesFromXml(attrs); mSeekBar = new SeekBar(context, attrs); mSeekBar.setMax(mMaxValue - mMinValue); mSeekBar.setOnSeekBarChangeListener(this); } private void setValuesFromXml(AttributeSet attrs) { mMaxValue = attrs.getAttributeIntValue(ANDROIDNS, "max", 100); mMinValue = attrs.getAttributeIntValue(PREFS, "min", 0); mUnitsLeft = getAttributeStringValue(attrs, PREFS, "unitsLeft", ""); String units = getAttributeStringValue(attrs, PREFS, "units", ""); mUnitsRight = getAttributeStringValue(attrs, PREFS, "unitsRight", units); try { String newInterval = attrs.getAttributeValue(PREFS, "interval"); if(newInterval != null) mInterval = Integer.parseInt(newInterval); } catch(Exception e) { Log.e(TAG, "Invalid interval value", e); } } private String getAttributeStringValue(AttributeSet attrs, String namespace, String name, String defaultValue) { String value = attrs.getAttributeValue(namespace, name); if(value == null) value = defaultValue; return value; } @Override protected View onCreateView(ViewGroup parent){ RelativeLayout layout = null; try { LayoutInflater mInflater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE); layout = (RelativeLayout)mInflater.inflate(R.layout.seek_bar_preference, parent, false); } catch(Exception e) { Log.e(TAG, "Error creating seek bar preference", e); } return layout; } @Override public void onBindView(View view) { super.onBindView(view); try { // move our seekbar to the new view we've been given ViewParent oldContainer = mSeekBar.getParent(); ViewGroup newContainer = (ViewGroup) view.findViewById(R.id.seekBarPrefBarContainer); if (oldContainer != newContainer) { // remove the seekbar from the old view if (oldContainer != null) { ((ViewGroup) oldContainer).removeView(mSeekBar); } // remove the existing seekbar (there may not be one) and add ours newContainer.removeAllViews(); newContainer.addView(mSeekBar, ViewGroup.LayoutParams.FILL_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT); } } catch(Exception ex) { Log.e(TAG, "Error binding view: " + ex.toString()); } updateView(view); } /** * Update a SeekBarPreference view with our current state * @param view */ protected void updateView(View view) { try { RelativeLayout layout = (RelativeLayout)view; mStatusText = (TextView)layout.findViewById(R.id.seekBarPrefValue); mStatusText.setText(String.valueOf(mCurrentValue)); mStatusText.setMinimumWidth(30); mSeekBar.setProgress(mCurrentValue - mMinValue); TextView unitsRight = (TextView)layout.findViewById(R.id.seekBarPrefUnitsRight); unitsRight.setText(mUnitsRight); TextView unitsLeft = (TextView)layout.findViewById(R.id.seekBarPrefUnitsLeft); unitsLeft.setText(mUnitsLeft); } catch(Exception e) { Log.e(TAG, "Error updating seek bar preference", e); } } public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) { int newValue = progress + mMinValue; if(newValue > mMaxValue) newValue = mMaxValue; else if(newValue < mMinValue) newValue = mMinValue; else if(mInterval != 1 && newValue % mInterval != 0) newValue = Math.round(((float)newValue)/mInterval)*mInterval; // change rejected, revert to the previous value if(!callChangeListener(newValue)){ seekBar.setProgress(mCurrentValue - mMinValue); return; } // change accepted, store it mCurrentValue = newValue; mStatusText.setText(String.valueOf(newValue)); persistInt(newValue); } public void onStartTrackingTouch(SeekBar seekBar) {} public void onStopTrackingTouch(SeekBar seekBar) { notifyChanged(); } @Override protected Object onGetDefaultValue(TypedArray ta, int index){ int defaultValue = ta.getInt(index, DEFAULT_VALUE); return defaultValue; } @Override protected void onSetInitialValue(boolean restoreValue, Object defaultValue) { if(restoreValue) { mCurrentValue = getPersistedInt(mCurrentValue); } else { int temp = 0; try { temp = (Integer)defaultValue; } catch(Exception ex) { Log.e(TAG, "Invalid default value: " + defaultValue.toString()); } persistInt(temp); mCurrentValue = temp; } } } Logcat: E/AndroidRuntime( 4525): FATAL EXCEPTION: main E/AndroidRuntime( 4525): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.ui.testapp/com.logic.testapp.SeekBarPreferen ce}: java.lang.InstantiationException: can't instantiate class com.logic.testapp.SeekBarPreference; no empty constructor E/AndroidRuntime( 4525): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1879) E/AndroidRuntime( 4525): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1980) E/AndroidRuntime( 4525): at android.app.ActivityThread.access$600(ActivityThread.java:122) E/AndroidRuntime( 4525): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1146) E/AndroidRuntime( 4525): at android.os.Handler.dispatchMessage(Handler.java:99) E/AndroidRuntime( 4525): at android.os.Looper.loop(Looper.java:137) E/AndroidRuntime( 4525): at android.app.ActivityThread.main(ActivityThread.java:4340) E/AndroidRuntime( 4525): at java.lang.reflect.Method.invokeNative(Native Method) E/AndroidRuntime( 4525): at java.lang.reflect.Method.invoke(Method.java:511) E/AndroidRuntime( 4525): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784) E/AndroidRuntime( 4525): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551) E/AndroidRuntime( 4525): at dalvik.system.NativeStart.main(Native Method) E/AndroidRuntime( 4525): Caused by: java.lang.InstantiationException: can't instantiate class com.logic.testapp.SeekBarPreference; no empty construc tor E/AndroidRuntime( 4525): at java.lang.Class.newInstanceImpl(Native Method) E/AndroidRuntime( 4525): at java.lang.Class.newInstance(Class.java:1319) E/AndroidRuntime( 4525): at android.app.Instrumentation.newActivity(Instrumentation.java:1023) E/AndroidRuntime( 4525): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1870) E/AndroidRuntime( 4525): ... 11 more W/ActivityManager( 84): Force finishing activity com.ui.testapp/com.logic.testapp.SeekBarPreference W/ActivityManager( 84): Force finishing activity com.ui.testapp/.MainScreen I/WindowManager( 84): createSurface Window{41a90320 paused=false}: DRAW NOW PENDING W/ActivityManager( 84): Activity pause timeout for ActivityRecord{4104a848 com.ui.testapp/com.logic.testapp.SeekBarPreference} W/NetworkManagementSocketTagger( 84): setKernelCountSet(10021, 1) failed with errno -2 I/WindowManager( 84): createSurface Window{412bcc10 com.android.launcher/com.android.launcher2.Launcher paused=false}: DRAW NOW PENDING W/NetworkManagementSocketTagger( 84): setKernelCountSet(10045, 0) failed with errno -2 I/Process ( 4525): Sending signal. PID: 4525 SIG: 9 I/ActivityManager( 84): Process com.ui.testapp (pid 4525) has died. I/WindowManager( 84): WIN DEATH: Window{41a6c9c0 com.ui.testapp/com.ui.testapp.MainScreen paused=true}

    Read the article

  • more radio problems * sighs * been at this for one week now

    - by jeansymolanza
    hi guys really i don't know what im doing wrong... i am trying to process multiple radios with mysql. the first step has involved me echoing the results on the process page. each time i select any radio option it simply displays the first row result. this is that i see after trying to submit the form: Notifications Thank you. The notifications have been updated successfully. statusid: 14 notc2: 1 Return this is the code for the form: <div style="padding: 15px;"> <span class="loginfail" style="font-size:24px; font-weight: bold">Notifications</span><p> <?php include("progress_insertcomment.php"); ?> <?php // Make a MySQL Connection mysql_select_db("speedycm_data") or die(mysql_error()); $query_comment = "select * from tbl_alert order by id desc limit 1"; $comment = mysql_query($query_comment, $speedycms) or die(mysql_error()); $row_comment = mysql_fetch_assoc($comment); $totalRows_comment = mysql_num_rows($comment); ?> <!--- add notification ---> <form method="post" action="<?php echo $_SERVER['PHP_SELF']; ?>"> <span id="sprytextarea1"> <textarea id='comment' name="comment" style="height: 75px; width:330px;"><?php echo $row_comment['comment']; ?></textarea> </span> <p> <button type="submit">Add</button> <input type="hidden" name="notc" value="1"/> </form> <!--- notification history ---> <form method="post" action="<?php echo $_SERVER['PHP_SELF']; ?>"> <table border="0" cellspacing="2" cellpadding="2"> <?php if ( $row_comment == 0 ) { echo "<span style='font-size: 11px;'>No current alerts.</span>"; } else { // Get all the data from the "example" table $result = mysql_query("SELECT * FROM tbl_alert ORDER BY id DESC") or die(mysql_error()); while($rows=mysql_fetch_array($result)){ ?> <tr> <td> <?php echo "<div class='bubble'><div class='pimped'> <blockquote>" . $rows['comment'] . " </blockquote></div> <cite><strong>" . $rows['user'] . "</strong> @ " . $rows['date'] . "</cite> <span style='font-size: 10px;'> <p> <a href='editalert.php?id=". $rows['id'] ."' class='form' >Edit</a>&nbsp;&#8226;&nbsp;<a href='deletealert.php?id=". $rows['id'] ."' class='form'>Delete</a> </span> </div> "; ?> </td> <td valign="top" align="center"><div style="padding-left: 30px;"><span style="font-size: 10px;">Completed?</span> <p class="field switch"> <!--- determine status of notification ---> <?php $status = $rows['status']; $id = $rows['id']; ?> <input type="radio" name="selstatus[<?php echo $id; ?>]" value="no" <?php if($status == 'yes') {echo 'checked';} else {echo '';} ?>/> <input type="radio" name="selstatus[<?php echo $id; ?>]" value="yes" <?php if($status == 'yes') {echo 'checked';} else {echo '';} ?>/> <input type="hidden" name="statusid" value="<?php echo $id; ?>"/> <label for="radio1" class="cb-enable <?php if($status == 'yes') {echo 'selected';} else {echo '';} ?>"><span>Yes</span></label> <label for="radio2" class="cb-disable <?php if($status == 'no') {echo 'selected';} else {echo '';} ?>"><span>No</span></label> </p> </div></td> </tr> <tr> <td></td> <?php } } ?> <td align="center"><div style="padding-left: 30px;"> <button type="submit">Update</button> <input type="hidden" name="notc2" value="1"/> </div></td> </tr> </table> </form> </div> this is the code for the processing page: <?php // 6) update notifications if (array_key_exists('notc2',$_POST)) { $update = $_POST['selstatus']; echo "<p style='font-size: 12px;'>Thank you. The notifications have been updated successfully.<p>"; foreach($_POST as $key => $value){ echo $key . ': ' . $value . '<br>'; } echo "<p><span style='font-size: 12px;'> <a onClick=\"history.go(-1)\" class='form'>Return</a></p> <p></span> "; exit; }; ?> how do i resolve this problem? please any help would be appreciated. i would like to display the id and value of the selected checkbox on the processing page before inserting it into the table. thanking you in advance. GOD BLESS

    Read the article

  • Using tinybutstrong templating system, how do I have a (secondary) mysql query (sub-block), inside a

    - by desbest
    This is the code that works well. $TBS->MergeBlock("items",$conn,"SELECT * FROM items WHERE categoryid = $getcategory"); and it has a good job of looping the items with no problem. <tr id="itemid_[items.id;block=tr]"> <td height="30"> <!-- <img src="move.png" align="left" style="margin-right: 8px;"> --> <div class="lowlight">[items.title] </div> </td> <td height="30"> <div class="editable" itemid="$item[id]">[items.quantity]</div> </td> <td height="30"> <!-- <img src="pencil.png" id="edititem"width="24" height="24"> --> &nbsp; &nbsp; &nbsp; &nbsp;<img src="icons/folder.png" id="category_[items.categoryid]";" class="changecategory" categoryid="[items.categoryid]" itemid="[items.id]" itemtitle="[items.title]" title="Change category" width="24" height="24"> &nbsp; &nbsp; &nbsp; &nbsp; <a href="index.php?category=[var.getcategory]&deleteitem=[items.id]" title="Delete item" onclick="return confirm('Are you sure you want to delete [items.title]?')"><img src="icons/trash.png" id="deleteitem" width="24" height="24"></a> </td> </tr> This is where the problem lies. In the table row I would like a secondary mysql merge block based on the id column that the primary (items) mysql table has. This means that ideally I would love to do this. $TBS->MergeBlock("fields",$conn,"SELECT * FROM items WHERE categoryid = [items.id]"); So then when I used [fields.value;block=div] inside the table row, it would pick up the a row from the fields table based on the primary mysql query. It would recognise what the id is for the merged block and perform a mysql query based on a variable that that block has. So that's what I would like to do and that's what I call a secondary mysql merge block. This is what I attempted by using the sub-blocks example and modifying it. index.html <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>TinyButStrong - Examples - subblocks</title> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> <link href="tbs_us_examples_0styles.css" rel="stylesheet" type="text/css"> <style type="text/css"> <!-- .border02 { border: 2px solid #39C; } .border03 { border: 2px solid #396; } --> </style> </head> <body> <table width="400" align="center" cellpadding="5" cellspacing="0" style="border-collapse:collapse;"> <tr> <td class="border02"><strong>Item name:</strong> [item.title;block=tr] , <strong>Item quantity:</strong> [item.quantity]<br> <table border="1" align="center" cellpadding="2" cellspacing="0"> <tr bgcolor="#CACACA"> <td width="30"><u>Position</u></td> <td width="150"><u>Attribute</u></td> <td width="50"><u>Value</u></td> <td width="100"><div align="center"><u>Date Number</u></div></td> </tr> <tr bgcolor="#F0F0F0"> <td>[field.#]</td> <td>[field.attribute;block=tr;p1=[item.id]] <br><b>[item.id]</b> </td> <td><div align="right">[field.value]</div></td> <td><div align="center">[field.datenumber;frm='mm-dd-yyyy']</div></td> </tr> </table> </td> </tr> </table> </body> </html> index.php <?php require_once('../stockman-v3/tbs_class.php'); require_once('../stockman-v3/config.php'); // Create data $TeamList[0] = array('team'=>'Eagle' ,'total'=>'458'); //{ $TeamList[0]['matches'][] = array('town'=>'London','score'=>'253','date'=>'1999-11-30'); $TeamList[0]['matches'][] = array('town'=>'Paris' ,'score'=>'145','date'=>'2002-07-24'); $TeamList[1] = array('team'=>'Goonies','total'=>'281'); $TeamList[1]['matches'][] = array('town'=>'New-York','score'=>'365','date'=>'2001-12-25'); $TeamList[1]['matches'][] = array('town'=>'Madrid' ,'score'=>'521','date'=>'2004-01-14'); // } $TeamList[2] = array('team'=>'MIB' ,'total'=>'615'); // { $TeamList[2]['matches'][] = array('town'=>'Dallas' ,'score'=>'362','date'=>'2001-01-02'); $TeamList[2]['matches'][] = array('town'=>'Lyon' ,'score'=>'321','date'=>'2002-11-17'); $TeamList[2]['matches'][] = array('town'=>'Washington','score'=>'245','date'=>'2003-08-24'); // } $TBS = new clsTinyButStrong; $TBS->LoadTemplate('index3.html'); // Automatic subblock $TBS->MergeBlock("item",$conn,"SELECT * FROM items"); $TBS->MergeBlock("field",$conn,"SELECT * FROM fields WHERE itemid='[%p1%]' "); $TBS->MergeBlock('teamKEY',$TeamList); // Subblock with a dynamic query //$TBS->MergeBlock('match','array','TeamList[%p1%][matches]'); $TBS->MergeBlock("match",$conn,"SELECT * FROM fields WHERE id='[%p1%]' "); $TBS->Show(); ?> please note what i am trying to do If I was to change $TBS->MergeBlock("field",$conn,"SELECT * FROM fields WHERE itemid='[%p1%]' "); to... $TBS->MergeBlock("field",$conn,"SELECT * FROM fields"); It would show all the items.

    Read the article

  • Using FiddlerCore to capture HTTP Requests with .NET

    - by Rick Strahl
    Over the last few weeks I’ve been working on my Web load testing utility West Wind WebSurge. One of the key components of a load testing tool is the ability to capture URLs effectively so that you can play them back later under load. One of the options in WebSurge for capturing URLs is to use its built-in capture tool which acts as an HTTP proxy to capture any HTTP and HTTPS traffic from most Windows HTTP clients, including Web Browsers as well as standalone Windows applications and services. To make this happen, I used Eric Lawrence’s awesome FiddlerCore library, which provides most of the functionality of his desktop Fiddler application, all rolled into an easy to use library that you can plug into your own applications. FiddlerCore makes it almost too easy to capture HTTP content! For WebSurge I needed to capture all HTTP traffic in order to capture the full HTTP request – URL, headers and any content posted by the client. The result of what I ended up creating is this semi-generic capture form: In this post I’m going to demonstrate how easy it is to use FiddlerCore to build this HTTP Capture Form.  If you want to jump right in here are the links to get Telerik’s Fiddler Core and the code for the demo provided here. FiddlerCore Download FiddlerCore on NuGet Show me the Code (WebSurge Integration code from GitHub) Download the WinForms Sample Form West Wind Web Surge (example implementation in live app) Note that FiddlerCore is bound by a license for commercial usage – see license.txt in the FiddlerCore distribution for details. Integrating FiddlerCore FiddlerCore is a library that simply plugs into your application. You can download it from the Telerik site and manually add the assemblies to your project, or you can simply install the NuGet package via:       PM> Install-Package FiddlerCore The library consists of the FiddlerCore.dll as well as a couple of support libraries (CertMaker.dll and BCMakeCert.dll) that are used for installing SSL certificates. I’ll have more on SSL captures and certificate installation later in this post. But first let’s see how easy it is to use FiddlerCore to capture HTTP content by looking at how to build the above capture form. Capturing HTTP Content Once the library is installed it’s super easy to hook up Fiddler functionality. Fiddler includes a number of static class methods on the FiddlerApplication object that can be called to hook up callback events as well as actual start monitoring HTTP URLs. In the following code directly lifted from WebSurge, I configure a few filter options on Form level object, from the user inputs shown on the form by assigning it to a capture options object. In the live application these settings are persisted configuration values, but in the demo they are one time values initialized and set on the form. Once these options are set, I hook up the AfterSessionComplete event to capture every URL that passes through the proxy after the request is completed and start up the Proxy service:void Start() { if (tbIgnoreResources.Checked) CaptureConfiguration.IgnoreResources = true; else CaptureConfiguration.IgnoreResources = false; string strProcId = txtProcessId.Text; if (strProcId.Contains('-')) strProcId = strProcId.Substring(strProcId.IndexOf('-') + 1).Trim(); strProcId = strProcId.Trim(); int procId = 0; if (!string.IsNullOrEmpty(strProcId)) { if (!int.TryParse(strProcId, out procId)) procId = 0; } CaptureConfiguration.ProcessId = procId; CaptureConfiguration.CaptureDomain = txtCaptureDomain.Text; FiddlerApplication.AfterSessionComplete += FiddlerApplication_AfterSessionComplete; FiddlerApplication.Startup(8888, true, true, true); } The key lines for FiddlerCore are just the last two lines of code that include the event hookup code as well as the Startup() method call. Here I only hook up to the AfterSessionComplete event but there are a number of other events that hook various stages of the HTTP request cycle you can also hook into. Other events include BeforeRequest, BeforeResponse, RequestHeadersAvailable, ResponseHeadersAvailable and so on. In my case I want to capture the request data and I actually have several options to capture this data. AfterSessionComplete is the last event that fires in the request sequence and it’s the most common choice to capture all request and response data. I could have used several other events, but AfterSessionComplete is one place where you can look both at the request and response data, so this will be the most common place to hook into if you’re capturing content. The implementation of AfterSessionComplete is responsible for capturing all HTTP request headers and it looks something like this:private void FiddlerApplication_AfterSessionComplete(Session sess) { // Ignore HTTPS connect requests if (sess.RequestMethod == "CONNECT") return; if (CaptureConfiguration.ProcessId > 0) { if (sess.LocalProcessID != 0 && sess.LocalProcessID != CaptureConfiguration.ProcessId) return; } if (!string.IsNullOrEmpty(CaptureConfiguration.CaptureDomain)) { if (sess.hostname.ToLower() != CaptureConfiguration.CaptureDomain.Trim().ToLower()) return; } if (CaptureConfiguration.IgnoreResources) { string url = sess.fullUrl.ToLower(); var extensions = CaptureConfiguration.ExtensionFilterExclusions; foreach (var ext in extensions) { if (url.Contains(ext)) return; } var filters = CaptureConfiguration.UrlFilterExclusions; foreach (var urlFilter in filters) { if (url.Contains(urlFilter)) return; } } if (sess == null || sess.oRequest == null || sess.oRequest.headers == null) return; string headers = sess.oRequest.headers.ToString(); var reqBody = sess.GetRequestBodyAsString(); // if you wanted to capture the response //string respHeaders = session.oResponse.headers.ToString(); //var respBody = session.GetResponseBodyAsString(); // replace the HTTP line to inject full URL string firstLine = sess.RequestMethod + " " + sess.fullUrl + " " + sess.oRequest.headers.HTTPVersion; int at = headers.IndexOf("\r\n"); if (at < 0) return; headers = firstLine + "\r\n" + headers.Substring(at + 1); string output = headers + "\r\n" + (!string.IsNullOrEmpty(reqBody) ? reqBody + "\r\n" : string.Empty) + Separator + "\r\n\r\n"; BeginInvoke(new Action<string>((text) => { txtCapture.AppendText(text); UpdateButtonStatus(); }), output); } The code starts by filtering out some requests based on the CaptureOptions I set before the capture is started. These options/filters are applied when requests actually come in. This is very useful to help narrow down the requests that are captured for playback based on options the user picked. I find it useful to limit requests to a certain domain for captures, as well as filtering out some request types like static resources – images, css, scripts etc. This is of course optional, but I think it’s a common scenario and WebSurge makes good use of this feature. AfterSessionComplete like other FiddlerCore events, provides a Session object parameter which contains all the request and response details. There are oRequest and oResponse objects to hold their respective data. In my case I’m interested in the raw request headers and body only, as you can see in the commented code you can also retrieve the response headers and body. Here the code captures the request headers and body and simply appends the output to the textbox on the screen. Note that the Fiddler events are asynchronous, so in order to display the content in the UI they have to be marshaled back the UI thread with BeginInvoke, which here simply takes the generated headers and appends it to the existing textbox test on the form. As each request is processed, the headers are captured and appended to the bottom of the textbox resulting in a Session HTTP capture in the format that Web Surge internally supports, which is basically raw request headers with a customized 1st HTTP Header line that includes the full URL rather than a server relative URL. When the capture is done the user can either copy the raw HTTP session to the clipboard, or directly save it to file. This raw capture format is the same format WebSurge and also Fiddler use to import/export request data. While this code is application specific, it demonstrates the kind of logic that you can easily apply to the request capture process, which is one of the reasonsof why FiddlerCore is so powerful. You get to choose what content you want to look up as part of your own application logic and you can then decide how to capture or use that data as part of your application. The actual captured data in this case is only a string. The user can edit the data by hand or in the the case of WebSurge, save it to disk and automatically open the captured session as a new load test. Stopping the FiddlerCore Proxy Finally to stop capturing requests you simply disconnect the event handler and call the FiddlerApplication.ShutDown() method:void Stop() { FiddlerApplication.AfterSessionComplete -= FiddlerApplication_AfterSessionComplete; if (FiddlerApplication.IsStarted()) FiddlerApplication.Shutdown(); } As you can see, adding HTTP capture functionality to an application is very straight forward. FiddlerCore offers tons of features I’m not even touching on here – I suspect basic captures are the most common scenario, but a lot of different things can be done with FiddlerCore’s simple API interface. Sky’s the limit! The source code for this sample capture form (WinForms) is provided as part of this article. Adding Fiddler Certificates with FiddlerCore One of the sticking points in West Wind WebSurge has been that if you wanted to capture HTTPS/SSL traffic, you needed to have the full version of Fiddler and have HTTPS decryption enabled. Essentially you had to use Fiddler to configure HTTPS decryption and the associated installation of the Fiddler local client certificate that is used for local decryption of incoming SSL traffic. While this works just fine, requiring to have Fiddler installed and then using a separate application to configure the SSL functionality isn’t ideal. Fortunately FiddlerCore actually includes the tools to register the Fiddler Certificate directly using FiddlerCore. Why does Fiddler need a Certificate in the first Place? Fiddler and FiddlerCore are essentially HTTP proxies which means they inject themselves into the HTTP conversation by re-routing HTTP traffic to a special HTTP port (8888 by default for Fiddler) and then forward the HTTP data to the original client. Fiddler injects itself as the system proxy in using the WinInet Windows settings  which are the same settings that Internet Explorer uses and that are configured in the Windows and Internet Explorer Internet Settings dialog. Most HTTP clients running on Windows pick up and apply these system level Proxy settings before establishing new HTTP connections and that’s why most clients automatically work once Fiddler – or FiddlerCore/WebSurge are running. For plain HTTP requests this just works – Fiddler intercepts the HTTP requests on the proxy port and then forwards them to the original port (80 for HTTP and 443 for SSL typically but it could be any port). For SSL however, this is not quite as simple – Fiddler can easily act as an HTTPS/SSL client to capture inbound requests from the server, but when it forwards the request to the client it has to also act as an SSL server and provide a certificate that the client trusts. This won’t be the original certificate from the remote site, but rather a custom local certificate that effectively simulates an SSL connection between the proxy and the client. If there is no custom certificate configured for Fiddler the SSL request fails with a certificate validation error. The key for this to work is that a custom certificate has to be installed that the HTTPS client trusts on the local machine. For a much more detailed description of the process you can check out Eric Lawrence’s blog post on Certificates. If you’re using the desktop version of Fiddler you can install a local certificate into the Windows certificate store. Fiddler proper does this from the Options menu: This operation does several things: It installs the Fiddler Root Certificate It sets trust to this Root Certificate A new client certificate is generated for each HTTPS site monitored Certificate Installation with FiddlerCore You can also provide this same functionality using FiddlerCore which includes a CertMaker class. Using CertMaker is straight forward to use and it provides an easy way to create some simple helpers that can install and uninstall a Fiddler Root certificate:public static bool InstallCertificate() { if (!CertMaker.rootCertExists()) { if (!CertMaker.createRootCert()) return false; if (!CertMaker.trustRootCert()) return false; } return true; } public static bool UninstallCertificate() { if (CertMaker.rootCertExists()) { if (!CertMaker.removeFiddlerGeneratedCerts(true)) return false; } return true; } InstallCertificate() works by first checking whether the root certificate is already installed and if it isn’t goes ahead and creates a new one. The process of creating the certificate is a two step process – first the actual certificate is created and then it’s moved into the certificate store to become trusted. I’m not sure why you’d ever split these operations up since a cert created without trust isn’t going to be of much value, but there are two distinct steps. When you trigger the trustRootCert() method, a message box will pop up on the desktop that lets you know that you’re about to trust a local private certificate. This is a security feature to ensure that you really want to trust the Fiddler root since you are essentially installing a man in the middle certificate. It’s quite safe to use this generated root certificate, because it’s been specifically generated for your machine and thus is not usable from external sources, the only way to use this certificate in a trusted way is from the local machine. IOW, unless somebody has physical access to your machine, there’s no useful way to hijack this certificate and use it for nefarious purposes (see Eric’s post for more details). Once the Root certificate has been installed, FiddlerCore/Fiddler create new certificates for each site that is connected to with HTTPS. You can end up with quite a few temporary certificates in your certificate store. To uninstall you can either use Fiddler and simply uncheck the Decrypt HTTPS traffic option followed by the remove Fiddler certificates button, or you can use FiddlerCore’s CertMaker.removeFiddlerGeneratedCerts() which removes the root cert and any of the intermediary certificates Fiddler created. Keep in mind that when you uninstall you uninstall the certificate for both FiddlerCore and Fiddler, so use UninstallCertificate() with care and realize that you might affect the Fiddler application’s operation by doing so as well. When to check for an installed Certificate Note that the check to see if the root certificate exists is pretty fast, while the actual process of installing the certificate is a relatively slow operation that even on a fast machine takes a few seconds. Further the trust operation pops up a message box so you probably don’t want to install the certificate repeatedly. Since the check for the root certificate is fast, you can easily put a call to InstallCertificate() in any capture startup code – in which case the certificate installation only triggers when a certificate is in fact not installed. Personally I like to make certificate installation explicit – just like Fiddler does, so in WebSurge I use a small drop down option on the menu to install or uninstall the SSL certificate:   This code calls the InstallCertificate and UnInstallCertificate functions respectively – the experience with this is similar to what you get in Fiddler with the extra dialog box popping up to prompt confirmation for installation of the root certificate. Once the cert is installed you can then capture SSL requests. There’s a gotcha however… Gotcha: FiddlerCore Certificates don’t stick by Default When I originally tried to use the Fiddler certificate installation I ran into an odd problem. I was able to install the certificate and immediately after installation was able to capture HTTPS requests. Then I would exit the application and come back in and try the same HTTPS capture again and it would fail due to a missing certificate. CertMaker.rootCertExists() would return false after every restart and if re-installed the certificate a new certificate would get added to the certificate store resulting in a bunch of duplicated root certificates with different keys. What the heck? CertMaker and BcMakeCert create non-sticky CertificatesI turns out that FiddlerCore by default uses different components from what the full version of Fiddler uses. Fiddler uses a Windows utility called MakeCert.exe to create the Fiddler Root certificate. FiddlerCore however installs the CertMaker.dll and BCMakeCert.dll assemblies, which use a different crypto library (Bouncy Castle) for certificate creation than MakeCert.exe which uses the Windows Crypto API. The assemblies provide support for non-windows operation for Fiddler under Mono, as well as support for some non-Windows certificate platforms like iOS and Android for decryption. The bottom line is that the FiddlerCore provided bouncy castle assemblies are not sticky by default as the certificates created with them are not cached as they are in Fiddler proper. To get certificates to ‘stick’ you have to explicitly cache the certificates in Fiddler’s internal preferences. A cache aware version of InstallCertificate looks something like this:public static bool InstallCertificate() { if (!CertMaker.rootCertExists()) { if (!CertMaker.createRootCert()) return false; if (!CertMaker.trustRootCert()) return false; App.Configuration.UrlCapture.Cert = FiddlerApplication.Prefs.GetStringPref("fiddler.certmaker.bc.cert", null); App.Configuration.UrlCapture.Key = FiddlerApplication.Prefs.GetStringPref("fiddler.certmaker.bc.key", null); } return true; } public static bool UninstallCertificate() { if (CertMaker.rootCertExists()) { if (!CertMaker.removeFiddlerGeneratedCerts(true)) return false; } App.Configuration.UrlCapture.Cert = null; App.Configuration.UrlCapture.Key = null; return true; } In this code I store the Fiddler cert and private key in an application configuration settings that’s stored with the application settings (App.Configuration.UrlCapture object). These settings automatically persist when WebSurge is shut down. The values are read out of Fiddler’s internal preferences store which is set after a new certificate has been created. Likewise I clear out the configuration settings when the certificate is uninstalled. In order for these setting to be used you have to also load the configuration settings into the Fiddler preferences *before* a call to rootCertExists() is made. I do this in the capture form’s constructor:public FiddlerCapture(StressTestForm form) { InitializeComponent(); CaptureConfiguration = App.Configuration.UrlCapture; MainForm = form; if (!string.IsNullOrEmpty(App.Configuration.UrlCapture.Cert)) { FiddlerApplication.Prefs.SetStringPref("fiddler.certmaker.bc.key", App.Configuration.UrlCapture.Key); FiddlerApplication.Prefs.SetStringPref("fiddler.certmaker.bc.cert", App.Configuration.UrlCapture.Cert); }} This is kind of a drag to do and not documented anywhere that I could find, so hopefully this will save you some grief if you want to work with the stock certificate logic that installs with FiddlerCore. MakeCert provides sticky Certificates and the same functionality as Fiddler But there’s actually an easier way. If you want to skip the above Fiddler preference configuration code in your application you can choose to distribute MakeCert.exe instead of certmaker.dll and bcmakecert.dll. When you use MakeCert.exe, the certificates settings are stored in Windows so they are available without any custom configuration inside of your application. It’s easier to integrate and as long as you run on Windows and you don’t need to support iOS or Android devices is simply easier to deal with. To integrate into your project, you can remove the reference to CertMaker.dll (and the BcMakeCert.dll assembly) from your project. Instead copy MakeCert.exe into your output folder. To make sure MakeCert.exe gets pushed out, include MakeCert.exe in your project and set the Build Action to None, and Copy to Output Directory to Copy if newer. Note that the CertMaker.dll reference in the project has been removed and on disk the files for Certmaker.dll, as well as the BCMakeCert.dll files on disk. Keep in mind that these DLLs are resources of the FiddlerCore NuGet package, so updating the package may end up pushing those files back into your project. Once MakeCert.exe is distributed FiddlerCore checks for it first before using the assemblies so as long as MakeCert.exe exists it’ll be used for certificate creation (at least on Windows). Summary FiddlerCore is a pretty sweet tool, and it’s absolutely awesome that we get to plug in most of the functionality of Fiddler right into our own applications. A few years back I tried to build this sort of functionality myself for an app and ended up giving up because it’s a big job to get HTTP right – especially if you need to support SSL. FiddlerCore now provides that functionality as a turnkey solution that can be plugged into your own apps easily. The only downside is FiddlerCore’s documentation for more advanced features like certificate installation which is pretty sketchy. While for the most part FiddlerCore’s feature set is easy to work with without any documentation, advanced features are often not intuitive to gleam by just using Intellisense or the FiddlerCore help file reference (which is not terribly useful). While Eric Lawrence is very responsive on his forum and on Twitter, there simply isn’t much useful documentation on Fiddler/FiddlerCore available online. If you run into trouble the forum is probably the first place to look and then ask a question if you can’t find the answer. The best documentation you can find is Eric’s Fiddler Book which covers a ton of functionality of Fiddler and FiddlerCore. The book is a great reference to Fiddler’s feature set as well as providing great insights into the HTTP protocol. The second half of the book that gets into the innards of HTTP is an excellent read for anybody who wants to know more about some of the more arcane aspects and special behaviors of HTTP – it’s well worth the read. While the book has tons of information in a very readable format, it’s unfortunately not a great reference as it’s hard to find things in the book and because it’s not available online you can’t electronically search for the great content in it. But it’s hard to complain about any of this given the obvious effort and love that’s gone into this awesome product for all of these years. A mighty big thanks to Eric Lawrence  for having created this useful tool that so many of us use all the time, and also to Telerik for picking up Fiddler/FiddlerCore and providing Eric the resources to support and improve this wonderful tool full time and keeping it free for all. Kudos! Resources FiddlerCore Download FiddlerCore NuGet Fiddler Capture Sample Form Fiddler Capture Form in West Wind WebSurge (GitHub) Eric Lawrence’s Fiddler Book© Rick Strahl, West Wind Technologies, 2005-2014Posted in .NET  HTTP   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

    Read the article

  • Entity Framework Code-First, OData & Windows Phone Client

    - by Jon Galloway
    Entity Framework Code-First is the coolest thing since sliced bread, Windows  Phone is the hottest thing since Tickle-Me-Elmo and OData is just too great to ignore. As part of the Full Stack project, we wanted to put them together, which turns out to be pretty easy… once you know how.   EF Code-First CTP5 is available now and there should be very few breaking changes in the release edition, which is due early in 2011.  Note: EF Code-First evolved rapidly and many of the existing documents and blog posts which were written with earlier versions, may now be obsolete or at least misleading.   Code-First? With traditional Entity Framework you start with a database and from that you generate “entities” – classes that bridge between the relational database and your object oriented program. With Code-First (Magic-Unicorn) (see Hanselman’s write up and this later write up by Scott Guthrie) the Entity Framework looks at classes you created and says “if I had created these classes, the database would have to have looked like this…” and creates the database for you! By deriving your entity collections from DbSet and exposing them via a class that derives from DbContext, you "turn on" database backing for your POCO with a minimum of code and no hidden designer or configuration files. POCO == Plain Old CLR Objects Your entity objects can be used throughout your applications - in web applications, console applications, Silverlight and Windows Phone applications, etc. In our case, we'll want to read and update data from a Windows Phone client application, so we'll expose the entities through a DataService and hook the Windows Phone client application to that data via proxies.  Piece of Pie.  Easy as cake. The Demo Architecture To see this at work, we’ll create an ASP.NET/MVC application which will act as the host for our Data Service.  We’ll create an incredibly simple data layer using EF Code-First on top of SQLCE4 and we’ll expose the data in a WCF Data Service using the oData protocol.  Our Windows Phone 7 client will instantiate  the data context via a URI and load the data asynchronously. Setting up the Server project with MVC 3, EF Code First, and SQL CE 4 Create a new application of type ASP.NET MVC 3 and name it DeadSimpleServer.  We need to add the latest SQLCE4 and Entity Framework Code First CTP's to our project. Fortunately, NuGet makes that really easy. Open the Package Manager Console (View / Other Windows / Package Manager Console) and type in "Install-Package EFCodeFirst.SqlServerCompact" at the PM> command prompt. Since NuGet handles dependencies for you, you'll see that it installs everything you need to use Entity Framework Code First in your project. PM> install-package EFCodeFirst.SqlServerCompact 'SQLCE (= 4.0.8435.1)' not installed. Attempting to retrieve dependency from source... Done 'EFCodeFirst (= 0.8)' not installed. Attempting to retrieve dependency from source... Done 'WebActivator (= 1.0.0.0)' not installed. Attempting to retrieve dependency from source... Done You are downloading SQLCE from Microsoft, the license agreement to which is available at http://173.203.67.148/licenses/SQLCE/EULA_ENU.rtf. Check the package for additional dependencies, which may come with their own license agreement(s). Your use of the package and dependencies constitutes your acceptance of their license agreements. If you do not accept the license agreement(s), then delete the relevant components from your device. Successfully installed 'SQLCE 4.0.8435.1' You are downloading EFCodeFirst from Microsoft, the license agreement to which is available at http://go.microsoft.com/fwlink/?LinkID=206497. Check the package for additional dependencies, which may come with their own license agreement(s). Your use of the package and dependencies constitutes your acceptance of their license agreements. If you do not accept the license agreement(s), then delete the relevant components from your device. Successfully installed 'EFCodeFirst 0.8' Successfully installed 'WebActivator 1.0.0.0' You are downloading EFCodeFirst.SqlServerCompact from Microsoft, the license agreement to which is available at http://173.203.67.148/licenses/SQLCE/EULA_ENU.rtf. Check the package for additional dependencies, which may come with their own license agreement(s). Your use of the package and dependencies constitutes your acceptance of their license agreements. If you do not accept the license agreement(s), then delete the relevant components from your device. Successfully installed 'EFCodeFirst.SqlServerCompact 0.8' Successfully added 'SQLCE 4.0.8435.1' to EfCodeFirst-CTP5 Successfully added 'EFCodeFirst 0.8' to EfCodeFirst-CTP5 Successfully added 'WebActivator 1.0.0.0' to EfCodeFirst-CTP5 Successfully added 'EFCodeFirst.SqlServerCompact 0.8' to EfCodeFirst-CTP5 Note: We're using SQLCE 4 with Entity Framework here because they work really well together from a development scenario, but you can of course use Entity Framework Code First with other databases supported by Entity framework. Creating The Model using EF Code First Now we can create our model class. Right-click the Models folder and select Add/Class. Name the Class Person.cs and add the following code: using System.Data.Entity; namespace DeadSimpleServer.Models { public class Person { public int ID { get; set; } public string Name { get; set; } } public class PersonContext : DbContext { public DbSet<Person> People { get; set; } } } Notice that the entity class Person has no special interfaces or base class. There's nothing special needed to make it work - it's just a POCO. The context we'll use to access the entities in the application is called PersonContext, but you could name it anything you wanted. The important thing is that it inherits DbContext and contains one or more DbSet which holds our entity collections. Adding Seed Data We need some testing data to expose from our service. The simplest way to get that into our database is to modify the CreateCeDatabaseIfNotExists class in AppStart_SQLCEEntityFramework.cs by adding some seed data to the Seed method: protected virtual void Seed( TContext context ) { var personContext = context as PersonContext; personContext.People.Add( new Person { ID = 1, Name = "George Washington" } ); personContext.People.Add( new Person { ID = 2, Name = "John Adams" } ); personContext.People.Add( new Person { ID = 3, Name = "Thomas Jefferson" } ); personContext.SaveChanges(); } The CreateCeDatabaseIfNotExists class name is pretty self-explanatory - when our DbContext is accessed and the database isn't found, a new one will be created and populated with the data in the Seed method. There's one more step to make that work - we need to uncomment a line in the Start method at the top of of the AppStart_SQLCEEntityFramework class and set the context name, as shown here, public static class AppStart_SQLCEEntityFramework { public static void Start() { DbDatabase.DefaultConnectionFactory = new SqlCeConnectionFactory("System.Data.SqlServerCe.4.0"); // Sets the default database initialization code for working with Sql Server Compact databases // Uncomment this line and replace CONTEXT_NAME with the name of your DbContext if you are // using your DbContext to create and manage your database DbDatabase.SetInitializer(new CreateCeDatabaseIfNotExists<PersonContext>()); } } Now our database and entity framework are set up, so we can expose data via WCF Data Services. Note: This is a bare-bones implementation with no administration screens. If you'd like to see how those are added, check out The Full Stack screencast series. Creating the oData Service using WCF Data Services Add a new WCF Data Service to the project (right-click the project / Add New Item / Web / WCF Data Service). We’ll be exposing all the data as read/write.  Remember to reconfigure to control and minimize access as appropriate for your own application. Open the code behind for your service. In our case, the service was called PersonTestDataService.svc so the code behind class file is PersonTestDataService.svc.cs. using System.Data.Services; using System.Data.Services.Common; using System.ServiceModel; using DeadSimpleServer.Models; namespace DeadSimpleServer { [ServiceBehavior( IncludeExceptionDetailInFaults = true )] public class PersonTestDataService : DataService<PersonContext> { // This method is called only once to initialize service-wide policies. public static void InitializeService( DataServiceConfiguration config ) { config.SetEntitySetAccessRule( "*", EntitySetRights.All ); config.DataServiceBehavior.MaxProtocolVersion = DataServiceProtocolVersion.V2; config.UseVerboseErrors = true; } } } We're enabling a few additional settings to make it easier to debug if you run into trouble. The ServiceBehavior attribute is set to include exception details in faults, and we're using verbose errors. You can remove both of these when your service is working, as your public production service shouldn't be revealing exception information. You can view the output of the service by running the application and browsing to http://localhost:[portnumber]/PersonTestDataService.svc/: <service xml:base="http://localhost:49786/PersonTestDataService.svc/" xmlns:atom="http://www.w3.org/2005/Atom" xmlns:app="http://www.w3.org/2007/app" xmlns="http://www.w3.org/2007/app"> <workspace> <atom:title>Default</atom:title> <collection href="People"> <atom:title>People</atom:title> </collection> </workspace> </service> This indicates that the service exposes one collection, which is accessible by browsing to http://localhost:[portnumber]/PersonTestDataService.svc/People <?xml version="1.0" encoding="iso-8859-1" standalone="yes"?> <feed xml:base=http://localhost:49786/PersonTestDataService.svc/ xmlns:d="http://schemas.microsoft.com/ado/2007/08/dataservices" xmlns:m="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata" xmlns="http://www.w3.org/2005/Atom"> <title type="text">People</title> <id>http://localhost:49786/PersonTestDataService.svc/People</id> <updated>2010-12-29T01:01:50Z</updated> <link rel="self" title="People" href="People" /> <entry> <id>http://localhost:49786/PersonTestDataService.svc/People(1)</id> <title type="text"></title> <updated>2010-12-29T01:01:50Z</updated> <author> <name /> </author> <link rel="edit" title="Person" href="People(1)" /> <category term="DeadSimpleServer.Models.Person" scheme="http://schemas.microsoft.com/ado/2007/08/dataservices/scheme" /> <content type="application/xml"> <m:properties> <d:ID m:type="Edm.Int32">1</d:ID> <d:Name>George Washington</d:Name> </m:properties> </content> </entry> <entry> ... </entry> </feed> Let's recap what we've done so far. But enough with services and XML - let's get this into our Windows Phone client application. Creating the DataServiceContext for the Client Use the latest DataSvcUtil.exe from http://odata.codeplex.com. As of today, that's in this download: http://odata.codeplex.com/releases/view/54698 You need to run it with a few options: /uri - This will point to the service URI. In this case, it's http://localhost:59342/PersonTestDataService.svc  Pick up the port number from your running server (e.g., the server formerly known as Cassini). /out - This is the DataServiceContext class that will be generated. You can name it whatever you'd like. /Version - should be set to 2.0 /DataServiceCollection - Include this flag to generate collections derived from the DataServiceCollection base, which brings in all the ObservableCollection goodness that handles your INotifyPropertyChanged events for you. Here's the console session from when we ran it: <ListBox x:Name="MainListBox" Margin="0,0,-12,0" ItemsSource="{Binding}" SelectionChanged="MainListBox_SelectionChanged"> Next, to keep things simple, change the Binding on the two TextBlocks within the DataTemplate to Name and ID, <ListBox x:Name="MainListBox" Margin="0,0,-12,0" ItemsSource="{Binding}" SelectionChanged="MainListBox_SelectionChanged"> <ListBox.ItemTemplate> <DataTemplate> <StackPanel Margin="0,0,0,17" Width="432"> <TextBlock Text="{Binding Name}" TextWrapping="Wrap" Style="{StaticResource PhoneTextExtraLargeStyle}" /> <TextBlock Text="{Binding ID}" TextWrapping="Wrap" Margin="12,-6,12,0" Style="{StaticResource PhoneTextSubtleStyle}" /> </StackPanel> </DataTemplate> </ListBox.ItemTemplate> </ListBox> Getting The Context In the code-behind you’ll first declare a member variable to hold the context from the Entity Framework. This is named using convention over configuration. The db type is Person and the context is of type PersonContext, You initialize it by providing the URI, in this case using the URL obtained from the Cassini web server, PersonContext context = new PersonContext( new Uri( "http://localhost:49786/PersonTestDataService.svc/" ) ); Create a second member variable of type DataServiceCollection<Person> but do not initialize it, DataServiceCollection<Person> people; In the constructor you’ll initialize the DataServiceCollection using the PersonContext, public MainPage() { InitializeComponent(); people = new DataServiceCollection<Person>( context ); Finally, you’ll load the people collection using the LoadAsync method, passing in the fully specified URI for the People collection in the web service, people.LoadAsync( new Uri( "http://localhost:49786/PersonTestDataService.svc/People" ) ); Note that this method runs asynchronously and when it is finished the people  collection is already populated. Thus, since we didn’t need or want to override any of the behavior we don’t implement the LoadCompleted. You can use the LoadCompleted event if you need to do any other UI updates, but you don't need to. The final code is as shown below: using System; using System.Data.Services.Client; using System.Windows; using System.Windows.Controls; using DeadSimpleServer.Models; using Microsoft.Phone.Controls; namespace WindowsPhoneODataTest { public partial class MainPage : PhoneApplicationPage { PersonContext context = new PersonContext( new Uri( "http://localhost:49786/PersonTestDataService.svc/" ) ); DataServiceCollection<Person> people; // Constructor public MainPage() { InitializeComponent(); // Set the data context of the listbox control to the sample data // DataContext = App.ViewModel; people = new DataServiceCollection<Person>( context ); people.LoadAsync( new Uri( "http://localhost:49786/PersonTestDataService.svc/People" ) ); DataContext = people; this.Loaded += new RoutedEventHandler( MainPage_Loaded ); } // Handle selection changed on ListBox private void MainListBox_SelectionChanged( object sender, SelectionChangedEventArgs e ) { // If selected index is -1 (no selection) do nothing if ( MainListBox.SelectedIndex == -1 ) return; // Navigate to the new page NavigationService.Navigate( new Uri( "/DetailsPage.xaml?selectedItem=" + MainListBox.SelectedIndex, UriKind.Relative ) ); // Reset selected index to -1 (no selection) MainListBox.SelectedIndex = -1; } // Load data for the ViewModel Items private void MainPage_Loaded( object sender, RoutedEventArgs e ) { if ( !App.ViewModel.IsDataLoaded ) { App.ViewModel.LoadData(); } } } } With people populated we can set it as the DataContext and run the application; you’ll find that the Name and ID are displayed in the list on the Mainpage. Here's how the pieces in the client fit together: Complete source code available here

    Read the article

  • C#/.NET Little Wonders: The Concurrent Collections (1 of 3)

    - by James Michael Hare
    Once again we consider some of the lesser known classes and keywords of C#.  In the next few weeks, we will discuss the concurrent collections and how they have changed the face of concurrent programming. This week’s post will begin with a general introduction and discuss the ConcurrentStack<T> and ConcurrentQueue<T>.  Then in the following post we’ll discuss the ConcurrentDictionary<T> and ConcurrentBag<T>.  Finally, we shall close on the third post with a discussion of the BlockingCollection<T>. For more of the "Little Wonders" posts, see the index here. A brief history of collections In the beginning was the .NET 1.0 Framework.  And out of this framework emerged the System.Collections namespace, and it was good.  It contained all the basic things a growing programming language needs like the ArrayList and Hashtable collections.  The main problem, of course, with these original collections is that they held items of type object which means you had to be disciplined enough to use them correctly or you could end up with runtime errors if you got an object of a type you weren't expecting. Then came .NET 2.0 and generics and our world changed forever!  With generics the C# language finally got an equivalent of the very powerful C++ templates.  As such, the System.Collections.Generic was born and we got type-safe versions of all are favorite collections.  The List<T> succeeded the ArrayList and the Dictionary<TKey,TValue> succeeded the Hashtable and so on.  The new versions of the library were not only safer because they checked types at compile-time, in many cases they were more performant as well.  So much so that it's Microsoft's recommendation that the System.Collections original collections only be used for backwards compatibility. So we as developers came to know and love the generic collections and took them into our hearts and embraced them.  The problem is, thread safety in both the original collections and the generic collections can be problematic, for very different reasons. Now, if you are only doing single-threaded development you may not care – after all, no locking is required.  Even if you do have multiple threads, if a collection is “load-once, read-many” you don’t need to do anything to protect that container from multi-threaded access, as illustrated below: 1: public static class OrderTypeTranslator 2: { 3: // because this dictionary is loaded once before it is ever accessed, we don't need to synchronize 4: // multi-threaded read access 5: private static readonly Dictionary<string, char> _translator = new Dictionary<string, char> 6: { 7: {"New", 'N'}, 8: {"Update", 'U'}, 9: {"Cancel", 'X'} 10: }; 11:  12: // the only public interface into the dictionary is for reading, so inherently thread-safe 13: public static char? Translate(string orderType) 14: { 15: char charValue; 16: if (_translator.TryGetValue(orderType, out charValue)) 17: { 18: return charValue; 19: } 20:  21: return null; 22: } 23: } Unfortunately, most of our computer science problems cannot get by with just single-threaded applications or with multi-threading in a load-once manner.  Looking at  today's trends, it's clear to see that computers are not so much getting faster because of faster processor speeds -- we've nearly reached the limits we can push through with today's technologies -- but more because we're adding more cores to the boxes.  With this new hardware paradigm, it is even more important to use multi-threaded applications to take full advantage of parallel processing to achieve higher application speeds. So let's look at how to use collections in a thread-safe manner. Using historical collections in a concurrent fashion The early .NET collections (System.Collections) had a Synchronized() static method that could be used to wrap the early collections to make them completely thread-safe.  This paradigm was dropped in the generic collections (System.Collections.Generic) because having a synchronized wrapper resulted in atomic locks for all operations, which could prove overkill in many multithreading situations.  Thus the paradigm shifted to having the user of the collection specify their own locking, usually with an external object: 1: public class OrderAggregator 2: { 3: private static readonly Dictionary<string, List<Order>> _orders = new Dictionary<string, List<Order>>(); 4: private static readonly _orderLock = new object(); 5:  6: public void Add(string accountNumber, Order newOrder) 7: { 8: List<Order> ordersForAccount; 9:  10: // a complex operation like this should all be protected 11: lock (_orderLock) 12: { 13: if (!_orders.TryGetValue(accountNumber, out ordersForAccount)) 14: { 15: _orders.Add(accountNumber, ordersForAccount = new List<Order>()); 16: } 17:  18: ordersForAccount.Add(newOrder); 19: } 20: } 21: } Notice how we’re performing several operations on the dictionary under one lock.  With the Synchronized() static methods of the early collections, you wouldn’t be able to specify this level of locking (a more macro-level).  So in the generic collections, it was decided that if a user needed synchronization, they could implement their own locking scheme instead so that they could provide synchronization as needed. The need for better concurrent access to collections Here’s the problem: it’s relatively easy to write a collection that locks itself down completely for access, but anything more complex than that can be difficult and error-prone to write, and much less to make it perform efficiently!  For example, what if you have a Dictionary that has frequent reads but in-frequent updates?  Do you want to lock down the entire Dictionary for every access?  This would be overkill and would prevent concurrent reads.  In such cases you could use something like a ReaderWriterLockSlim which allows for multiple readers in a lock, and then once a writer grabs the lock it blocks all further readers until the writer is done (in a nutshell).  This is all very complex stuff to consider. Fortunately, this is where the Concurrent Collections come in.  The Parallel Computing Platform team at Microsoft went through great pains to determine how to make a set of concurrent collections that would have the best performance characteristics for general case multi-threaded use. Now, as in all things involving threading, you should always make sure you evaluate all your container options based on the particular usage scenario and the degree of parallelism you wish to acheive. This article should not be taken to understand that these collections are always supperior to the generic collections. Each fills a particular need for a particular situation. Understanding what each container is optimized for is key to the success of your application whether it be single-threaded or multi-threaded. General points to consider with the concurrent collections The MSDN points out that the concurrent collections all support the ICollection interface. However, since the collections are already synchronized, the IsSynchronized property always returns false, and SyncRoot always returns null.  Thus you should not attempt to use these properties for synchronization purposes. Note that since the concurrent collections also may have different operations than the traditional data structures you may be used to.  Now you may ask why they did this, but it was done out of necessity to keep operations safe and atomic.  For example, in order to do a Pop() on a stack you have to know the stack is non-empty, but between the time you check the stack’s IsEmpty property and then do the Pop() another thread may have come in and made the stack empty!  This is why some of the traditional operations have been changed to make them safe for concurrent use. In addition, some properties and methods in the concurrent collections achieve concurrency by creating a snapshot of the collection, which means that some operations that were traditionally O(1) may now be O(n) in the concurrent models.  I’ll try to point these out as we talk about each collection so you can be aware of any potential performance impacts.  Finally, all the concurrent containers are safe for enumeration even while being modified, but some of the containers support this in different ways (snapshot vs. dirty iteration).  Once again I’ll highlight how thread-safe enumeration works for each collection. ConcurrentStack<T>: The thread-safe LIFO container The ConcurrentStack<T> is the thread-safe counterpart to the System.Collections.Generic.Stack<T>, which as you may remember is your standard last-in-first-out container.  If you think of algorithms that favor stack usage (for example, depth-first searches of graphs and trees) then you can see how using a thread-safe stack would be of benefit. The ConcurrentStack<T> achieves thread-safe access by using System.Threading.Interlocked operations.  This means that the multi-threaded access to the stack requires no traditional locking and is very, very fast! For the most part, the ConcurrentStack<T> behaves like it’s Stack<T> counterpart with a few differences: Pop() was removed in favor of TryPop() Returns true if an item existed and was popped and false if empty. PushRange() and TryPopRange() were added Allows you to push multiple items and pop multiple items atomically. Count takes a snapshot of the stack and then counts the items. This means it is a O(n) operation, if you just want to check for an empty stack, call IsEmpty instead which is O(1). ToArray() and GetEnumerator() both also take snapshots. This means that iteration over a stack will give you a static view at the time of the call and will not reflect updates. Pushing on a ConcurrentStack<T> works just like you’d expect except for the aforementioned PushRange() method that was added to allow you to push a range of items concurrently. 1: var stack = new ConcurrentStack<string>(); 2:  3: // adding to stack is much the same as before 4: stack.Push("First"); 5:  6: // but you can also push multiple items in one atomic operation (no interleaves) 7: stack.PushRange(new [] { "Second", "Third", "Fourth" }); For looking at the top item of the stack (without removing it) the Peek() method has been removed in favor of a TryPeek().  This is because in order to do a peek the stack must be non-empty, but between the time you check for empty and the time you execute the peek the stack contents may have changed.  Thus the TryPeek() was created to be an atomic check for empty, and then peek if not empty: 1: // to look at top item of stack without removing it, can use TryPeek. 2: // Note that there is no Peek(), this is because you need to check for empty first. TryPeek does. 3: string item; 4: if (stack.TryPeek(out item)) 5: { 6: Console.WriteLine("Top item was " + item); 7: } 8: else 9: { 10: Console.WriteLine("Stack was empty."); 11: } Finally, to remove items from the stack, we have the TryPop() for single, and TryPopRange() for multiple items.  Just like the TryPeek(), these operations replace Pop() since we need to ensure atomically that the stack is non-empty before we pop from it: 1: // to remove items, use TryPop or TryPopRange to get multiple items atomically (no interleaves) 2: if (stack.TryPop(out item)) 3: { 4: Console.WriteLine("Popped " + item); 5: } 6:  7: // TryPopRange will only pop up to the number of spaces in the array, the actual number popped is returned. 8: var poppedItems = new string[2]; 9: int numPopped = stack.TryPopRange(poppedItems); 10:  11: foreach (var theItem in poppedItems.Take(numPopped)) 12: { 13: Console.WriteLine("Popped " + theItem); 14: } Finally, note that as stated before, GetEnumerator() and ToArray() gets a snapshot of the data at the time of the call.  That means if you are enumerating the stack you will get a snapshot of the stack at the time of the call.  This is illustrated below: 1: var stack = new ConcurrentStack<string>(); 2:  3: // adding to stack is much the same as before 4: stack.Push("First"); 5:  6: var results = stack.GetEnumerator(); 7:  8: // but you can also push multiple items in one atomic operation (no interleaves) 9: stack.PushRange(new [] { "Second", "Third", "Fourth" }); 10:  11: while(results.MoveNext()) 12: { 13: Console.WriteLine("Stack only has: " + results.Current); 14: } The only item that will be printed out in the above code is "First" because the snapshot was taken before the other items were added. This may sound like an issue, but it’s really for safety and is more correct.  You don’t want to enumerate a stack and have half a view of the stack before an update and half a view of the stack after an update, after all.  In addition, note that this is still thread-safe, whereas iterating through a non-concurrent collection while updating it in the old collections would cause an exception. ConcurrentQueue<T>: The thread-safe FIFO container The ConcurrentQueue<T> is the thread-safe counterpart of the System.Collections.Generic.Queue<T> class.  The concurrent queue uses an underlying list of small arrays and lock-free System.Threading.Interlocked operations on the head and tail arrays.  Once again, this allows us to do thread-safe operations without the need for heavy locks! The ConcurrentQueue<T> (like the ConcurrentStack<T>) has some departures from the non-concurrent counterpart.  Most notably: Dequeue() was removed in favor of TryDequeue(). Returns true if an item existed and was dequeued and false if empty. Count does not take a snapshot It subtracts the head and tail index to get the count.  This results overall in a O(1) complexity which is quite good.  It’s still recommended, however, that for empty checks you call IsEmpty instead of comparing Count to zero. ToArray() and GetEnumerator() both take snapshots. This means that iteration over a queue will give you a static view at the time of the call and will not reflect updates. The Enqueue() method on the ConcurrentQueue<T> works much the same as the generic Queue<T>: 1: var queue = new ConcurrentQueue<string>(); 2:  3: // adding to queue is much the same as before 4: queue.Enqueue("First"); 5: queue.Enqueue("Second"); 6: queue.Enqueue("Third"); For front item access, the TryPeek() method must be used to attempt to see the first item if the queue.  There is no Peek() method since, as you’ll remember, we can only peek on a non-empty queue, so we must have an atomic TryPeek() that checks for empty and then returns the first item if the queue is non-empty. 1: // to look at first item in queue without removing it, can use TryPeek. 2: // Note that there is no Peek(), this is because you need to check for empty first. TryPeek does. 3: string item; 4: if (queue.TryPeek(out item)) 5: { 6: Console.WriteLine("First item was " + item); 7: } 8: else 9: { 10: Console.WriteLine("Queue was empty."); 11: } Then, to remove items you use TryDequeue().  Once again this is for the same reason we have TryPeek() and not Peek(): 1: // to remove items, use TryDequeue. If queue is empty returns false. 2: if (queue.TryDequeue(out item)) 3: { 4: Console.WriteLine("Dequeued first item " + item); 5: } Just like the concurrent stack, the ConcurrentQueue<T> takes a snapshot when you call ToArray() or GetEnumerator() which means that subsequent updates to the queue will not be seen when you iterate over the results.  Thus once again the code below will only show the first item, since the other items were added after the snapshot. 1: var queue = new ConcurrentQueue<string>(); 2:  3: // adding to queue is much the same as before 4: queue.Enqueue("First"); 5:  6: var iterator = queue.GetEnumerator(); 7:  8: queue.Enqueue("Second"); 9: queue.Enqueue("Third"); 10:  11: // only shows First 12: while (iterator.MoveNext()) 13: { 14: Console.WriteLine("Dequeued item " + iterator.Current); 15: } Using collections concurrently You’ll notice in the examples above I stuck to using single-threaded examples so as to make them deterministic and the results obvious.  Of course, if we used these collections in a truly multi-threaded way the results would be less deterministic, but would still be thread-safe and with no locking on your part required! For example, say you have an order processor that takes an IEnumerable<Order> and handles each other in a multi-threaded fashion, then groups the responses together in a concurrent collection for aggregation.  This can be done easily with the TPL’s Parallel.ForEach(): 1: public static IEnumerable<OrderResult> ProcessOrders(IEnumerable<Order> orderList) 2: { 3: var proxy = new OrderProxy(); 4: var results = new ConcurrentQueue<OrderResult>(); 5:  6: // notice that we can process all these in parallel and put the results 7: // into our concurrent collection without needing any external locking! 8: Parallel.ForEach(orderList, 9: order => 10: { 11: var result = proxy.PlaceOrder(order); 12:  13: results.Enqueue(result); 14: }); 15:  16: return results; 17: } Summary Obviously, if you do not need multi-threaded safety, you don’t need to use these collections, but when you do need multi-threaded collections these are just the ticket! The plethora of features (I always think of the movie The Three Amigos when I say plethora) built into these containers and the amazing way they acheive thread-safe access in an efficient manner is wonderful to behold. Stay tuned next week where we’ll continue our discussion with the ConcurrentBag<T> and the ConcurrentDictionary<TKey,TValue>. For some excellent information on the performance of the concurrent collections and how they perform compared to a traditional brute-force locking strategy, see this wonderful whitepaper by the Microsoft Parallel Computing Platform team here.   Tweet Technorati Tags: C#,.NET,Concurrent Collections,Collections,Multi-Threading,Little Wonders,BlackRabbitCoder,James Michael Hare

    Read the article

  • SQL Monitor’s data repository: Alerts

    - by Chris Lambrou
    In my previous post, I introduced the SQL Monitor data repository, and described how the monitored objects are stored in a hierarchy in the data schema, in a series of tables with a _Keys suffix. In this post I had planned to describe how the actual data for the monitored objects is stored in corresponding tables with _StableSamples and _UnstableSamples suffixes. However, I’m going to postpone that until my next post, as I’ve had a request from a SQL Monitor user to explain how alerts are stored. In the SQL Monitor data repository, alerts are stored in tables belonging to the alert schema, which contains the following five tables: alert.Alert alert.Alert_Cleared alert.Alert_Comment alert.Alert_Severity alert.Alert_Type In this post, I’m only going to cover the alert.Alert and alert.Alert_Type tables. I may cover the other three tables in a later post. The most important table in this schema is alert.Alert, as each row in this table corresponds to a single alert. So let’s have a look at it. SELECT TOP 100 AlertId, AlertType, TargetObject, [Read], SubType FROM alert.Alert ORDER BY AlertId DESC;  AlertIdAlertTypeTargetObjectReadSubType 165550397:Cluster,1,4:Name,s29:srp-mr03.testnet.red-gate.com,9:SqlServer,1,4:Name,s0:,10 265549387:Cluster,1,4:Name,s29:srp-mr03.testnet.red-gate.com,7:Machine,1,4:Name,s0:,10 365548187:Cluster,1,4:Name,s7:granger,9:SqlServer,1,4:Name,s0:,8:Database,1,4:Name,s15:FavouriteThings,00 465547157:Cluster,1,4:Name,s7:granger,9:SqlServer,1,4:Name,s0:,8:Database,1,4:Name,s15:FavouriteThings,00 565546147:Cluster,1,4:Name,s7:granger,9:SqlServer,1,4:Name,s0:,8:Database,1,4:Name,s15:FavouriteThings,00 665545187:Cluster,1,4:Name,s7:granger,9:SqlServer,1,4:Name,s0:,8:Database,1,4:Name,s14:SqlMonitorData,00 765544157:Cluster,1,4:Name,s7:granger,9:SqlServer,1,4:Name,s0:,8:Database,1,4:Name,s14:SqlMonitorData,00 865543147:Cluster,1,4:Name,s7:granger,9:SqlServer,1,4:Name,s0:,8:Database,1,4:Name,s14:SqlMonitorData,00 965542187:Cluster,1,4:Name,s7:granger,9:SqlServer,1,4:Name,s0:,8:Database,1,4:Name,s4:msdb,00 1065541147:Cluster,1,4:Name,s7:granger,9:SqlServer,1,4:Name,s0:,8:Database,1,4:Name,s4:msdb,00 11…     So what are we seeing here, then? Well, AlertId is an auto-incrementing identity column, so ORDER BY AlertId DESC ensures that we see the most recent alerts first. AlertType indicates the type of each alert, such as Job failed (6), Backup overdue (14) or Long-running query (12). The TargetObject column indicates which monitored object the alert is associated with. The Read column acts as a flag to indicate whether or not the alert has been read. And finally the SubType column is used in the case of a Custom metric (40) alert, to indicate which custom metric the alert pertains to. Okay, now lets look at some of those columns in more detail. The AlertType column is an easy one to start with, and it brings use nicely to the next table, data.Alert_Type. Let’s have a look at what’s in this table: SELECT AlertType, Event, Monitoring, Name, Description FROM alert.Alert_Type ORDER BY AlertType;  AlertTypeEventMonitoringNameDescription 1100Processor utilizationProcessor utilization (CPU) on a host machine stays above a threshold percentage for longer than a specified duration 2210SQL Server error log entryAn error is written to the SQL Server error log with a severity level above a specified value. 3310Cluster failoverThe active cluster node fails, causing the SQL Server instance to switch nodes. 4410DeadlockSQL deadlock occurs. 5500Processor under-utilizationProcessor utilization (CPU) on a host machine remains below a threshold percentage for longer than a specified duration 6610Job failedA job does not complete successfully (the job returns an error code). 7700Machine unreachableHost machine (Windows server) cannot be contacted on the network. 8800SQL Server instance unreachableThe SQL Server instance is not running or cannot be contacted on the network. 9900Disk spaceDisk space used on a logical disk drive is above a defined threshold for longer than a specified duration. 101000Physical memoryPhysical memory (RAM) used on the host machine stays above a threshold percentage for longer than a specified duration. 111100Blocked processSQL process is blocked for longer than a specified duration. 121200Long-running queryA SQL query runs for longer than a specified duration. 131400Backup overdueNo full backup exists, or the last full backup is older than a specified time. 141500Log backup overdueNo log backup exists, or the last log backup is older than a specified time. 151600Database unavailableDatabase changes from Online to any other state. 161700Page verificationTorn Page Detection or Page Checksum is not enabled for a database. 171800Integrity check overdueNo entry for an integrity check (DBCC DBINFO returns no date for dbi_dbccLastKnownGood field), or the last check is older than a specified time. 181900Fragmented indexesFragmentation level of one or more indexes is above a threshold percentage. 192400Job duration unusualThe duration of a SQL job duration deviates from its baseline duration by more than a threshold percentage. 202501Clock skewSystem clock time on the Base Monitor computer differs from the system clock time on a monitored SQL Server host machine by a specified number of seconds. 212700SQL Server Agent Service statusThe SQL Server Agent Service status matches the status specified. 222800SQL Server Reporting Service statusThe SQL Server Reporting Service status matches the status specified. 232900SQL Server Full Text Search Service statusThe SQL Server Full Text Search Service status matches the status specified. 243000SQL Server Analysis Service statusThe SQL Server Analysis Service status matches the status specified. 253100SQL Server Integration Service statusThe SQL Server Integration Service status matches the status specified. 263300SQL Server Browser Service statusThe SQL Server Browser Service status matches the status specified. 273400SQL Server VSS Writer Service statusThe SQL Server VSS Writer status matches the status specified. 283501Deadlock trace flag disabledThe monitored SQL Server’s trace flag cannot be enabled. 293600Monitoring stopped (host machine credentials)SQL Monitor cannot contact the host machine because authentication failed. 303700Monitoring stopped (SQL Server credentials)SQL Monitor cannot contact the SQL Server instance because authentication failed. 313800Monitoring error (host machine data collection)SQL Monitor cannot collect data from the host machine. 323900Monitoring error (SQL Server data collection)SQL Monitor cannot collect data from the SQL Server instance. 334000Custom metricThe custom metric value has passed an alert threshold. 344100Custom metric collection errorSQL Monitor cannot collect custom metric data from the target object. Basically, alert.Alert_Type is just a big reference table containing information about the 34 different alert types supported by SQL Monitor (note that the largest id is 41, not 34 – some alert types have been retired since SQL Monitor was first developed). The Name and Description columns are self evident, and I’m going to skip over the Event and Monitoring columns as they’re not very interesting. The AlertId column is the primary key, and is referenced by AlertId in the alert.Alert table. As such, we can rewrite our earlier query to join these two tables, in order to provide a more readable view of the alerts: SELECT TOP 100 AlertId, Name, TargetObject, [Read], SubType FROM alert.Alert a JOIN alert.Alert_Type at ON a.AlertType = at.AlertType ORDER BY AlertId DESC;  AlertIdNameTargetObjectReadSubType 165550Monitoring error (SQL Server data collection)7:Cluster,1,4:Name,s29:srp-mr03.testnet.red-gate.com,9:SqlServer,1,4:Name,s0:,00 265549Monitoring error (host machine data collection)7:Cluster,1,4:Name,s29:srp-mr03.testnet.red-gate.com,7:Machine,1,4:Name,s0:,00 365548Integrity check overdue7:Cluster,1,4:Name,s7:granger,9:SqlServer,1,4:Name,s0:,8:Database,1,4:Name,s15:FavouriteThings,00 465547Log backup overdue7:Cluster,1,4:Name,s7:granger,9:SqlServer,1,4:Name,s0:,8:Database,1,4:Name,s15:FavouriteThings,00 565546Backup overdue7:Cluster,1,4:Name,s7:granger,9:SqlServer,1,4:Name,s0:,8:Database,1,4:Name,s15:FavouriteThings,00 665545Integrity check overdue7:Cluster,1,4:Name,s7:granger,9:SqlServer,1,4:Name,s0:,8:Database,1,4:Name,s14:SqlMonitorData,00 765544Log backup overdue7:Cluster,1,4:Name,s7:granger,9:SqlServer,1,4:Name,s0:,8:Database,1,4:Name,s14:SqlMonitorData,00 865543Backup overdue7:Cluster,1,4:Name,s7:granger,9:SqlServer,1,4:Name,s0:,8:Database,1,4:Name,s14:SqlMonitorData,00 965542Integrity check overdue7:Cluster,1,4:Name,s7:granger,9:SqlServer,1,4:Name,s0:,8:Database,1,4:Name,s4:msdb,00 1065541Backup overdue7:Cluster,1,4:Name,s7:granger,9:SqlServer,1,4:Name,s0:,8:Database,1,4:Name,s4:msdb,00 Okay, the next column to discuss in the alert.Alert table is TargetObject. Oh boy, this one’s a bit tricky! The TargetObject of an alert is a serialized string representation of the position in the monitored object hierarchy of the object to which the alert pertains. The serialization format is somewhat convenient for parsing in the C# source code of SQL Monitor, and has some helpful characteristics, but it’s probably very awkward to manipulate in T-SQL. I could document the serialization format here, but it would be very dry reading, so perhaps it’s best to consider an example from the table above. Have a look at the alert with an AlertID of 65543. It’s a Backup overdue alert for the SqlMonitorData database running on the default instance of granger, my laptop. Each different alert type is associated with a specific type of monitored object in the object hierarchy (I described the hierarchy in my previous post). The Backup overdue alert is associated with databases, whose position in the object hierarchy is root → Cluster → SqlServer → Database. The TargetObject value identifies the target object by specifying the key properties at each level in the hierarchy, thus: Cluster: Name = "granger" SqlServer: Name = "" (an empty string, denoting the default instance) Database: Name = "SqlMonitorData" Well, look at the actual TargetObject value for this alert: "7:Cluster,1,4:Name,s7:granger,9:SqlServer,1,4:Name,s0:,8:Database,1,4:Name,s14:SqlMonitorData,". It is indeed composed of three parts, one for each level in the hierarchy: Cluster: "7:Cluster,1,4:Name,s7:granger," SqlServer: "9:SqlServer,1,4:Name,s0:," Database: "8:Database,1,4:Name,s14:SqlMonitorData," Each part is handled in exactly the same way, so let’s concentrate on the first part, "7:Cluster,1,4:Name,s7:granger,". It comprises the following: "7:Cluster," – This identifies the level in the hierarchy. "1," – This indicates how many different key properties there are to uniquely identify a cluster (we saw in my last post that each cluster is identified by a single property, its Name). "4:Name,s14:SqlMonitorData," – This represents the Name property, and its corresponding value, SqlMonitorData. It’s split up like this: "4:Name," – Indicates the name of the key property. "s" – Indicates the type of the key property, in this case, it’s a string. "14:SqlMonitorData," – Indicates the value of the property. At this point, you might be wondering about the format of some of these strings. Why is the string "Cluster" stored as "7:Cluster,"? Well an encoding scheme is used, which consists of the following: "7" – This is the length of the string "Cluster" ":" – This is a delimiter between the length of the string and the actual string’s contents. "Cluster" – This is the string itself. 7 characters. "," – This is a final terminating character that indicates the end of the encoded string. You can see that "4:Name,", "8:Database," and "14:SqlMonitorData," also conform to the same encoding scheme. In the example above, the "s" character is used to indicate that the value of the Name property is a string. If you explore the TargetObject property of alerts in your own SQL Monitor data repository, you might find other characters used for other non-string key property values. The different value types you might possibly encounter are as follows: "I" – Denotes a bigint value. For example, "I65432,". "g" – Denotes a GUID value. For example, "g32116732-63ae-4ab5-bd34-7dfdfb084c18,". "d" – Denotes a datetime value. For example, "d634815384796832438,". The value is stored as a bigint, rather than a native SQL datetime value. I’ll describe how datetime values are handled in the SQL Monitor data repostory in a future post. I suggest you have a look at the alerts in your own SQL Monitor data repository for further examples, so you can see how the TargetObject values are composed for each of the different types of alert. Let me give one further example, though, that represents a Custom metric alert, as this will help in describing the final column of interest in the alert.Alert table, SubType. Let me show you the alert I’m interested in: SELECT AlertId, a.AlertType, Name, TargetObject, [Read], SubType FROM alert.Alert a JOIN alert.Alert_Type at ON a.AlertType = at.AlertType WHERE AlertId = 65769;  AlertIdAlertTypeNameTargetObjectReadSubType 16576940Custom metric7:Cluster,1,4:Name,s7:granger,9:SqlServer,1,4:Name,s0:,8:Database,1,4:Name,s6:master,12:CustomMetric,1,8:MetricId,I2,02 An AlertType value of 40 corresponds to the Custom metric alert type. The Name taken from the alert.Alert_Type table is simply Custom metric, but this doesn’t tell us anything about the specific custom metric that this alert pertains to. That’s where the SubType value comes in. For custom metric alerts, this provides us with the Id of the specific custom alert definition that can be found in the settings.CustomAlertDefinitions table. I don’t really want to delve into custom alert definitions yet (maybe in a later post), but an extra join in the previous query shows us that this alert pertains to the CPU pressure (avg runnable task count) custom metric alert. SELECT AlertId, a.AlertType, at.Name, cad.Name AS CustomAlertName, TargetObject, [Read], SubType FROM alert.Alert a JOIN alert.Alert_Type at ON a.AlertType = at.AlertType JOIN settings.CustomAlertDefinitions cad ON a.SubType = cad.Id WHERE AlertId = 65769;  AlertIdAlertTypeNameCustomAlertNameTargetObjectReadSubType 16576940Custom metricCPU pressure (avg runnable task count)7:Cluster,1,4:Name,s7:granger,9:SqlServer,1,4:Name,s0:,8:Database,1,4:Name,s6:master,12:CustomMetric,1,8:MetricId,I2,02 The TargetObject value in this case breaks down like this: "7:Cluster,1,4:Name,s7:granger," – Cluster named "granger". "9:SqlServer,1,4:Name,s0:," – SqlServer named "" (the default instance). "8:Database,1,4:Name,s6:master," – Database named "master". "12:CustomMetric,1,8:MetricId,I2," – Custom metric with an Id of 2. Note that the hierarchy for a custom metric is slightly different compared to the earlier Backup overdue alert. It’s root → Cluster → SqlServer → Database → CustomMetric. Also notice that, unlike Cluster, SqlServer and Database, the key property for CustomMetric is called MetricId (not Name), and the value is a bigint (not a string). Finally, delving into the custom metric tables is beyond the scope of this post, but for the sake of avoiding any future confusion, I’d like to point out that whilst the SubType references a custom alert definition, the MetricID value embedded in the TargetObject value references a custom metric definition. Although in this case both the custom metric definition and custom alert definition share the same Id value of 2, this is not generally the case. Okay, that’s enough for now, not least because as I’m typing this, it’s almost 2am, I have to go to work tomorrow, and my alarm is set for 6am – eek! In my next post, I’ll either cover the remaining three tables in the alert schema, or I’ll delve into the way SQL Monitor stores its monitoring data, as I’d originally planned to cover in this post.

    Read the article

  • Insert Record by Drag & Drop from ADF Tree to ADF Tree Table

    - by arul.wilson(at)oracle.com
    If you want to create record based on the values Dragged from ADF Tree and Dropped on a ADF Tree Table, then here you go.UseCase DescriptionUser Drags a tree node from ADF Tree and Drops it on a ADF Tree Table node. A new row gets added in the Tree Table based on the source tree node, subsequently a record gets added to the database table on which Tree table in based on.Following description helps to achieve this using ADF BC.Run the DragDropSchema.sql to create required tables.Create Business Components from tables (PRODUCTS, COMPONENTS, SUB_COMPONENTS, USERS, USER_COMPONENTS) created above.Add custom method to App Module Impl, this method will be used to insert record from view layer.   public String createUserComponents(String p_bugdbId, String p_productId, String p_componentId, String p_subComponentId){    Row newUserComponentsRow = this.getUserComponentsView1().createRow();    try {      newUserComponentsRow.setAttribute("Bugdbid", p_bugdbId);      newUserComponentsRow.setAttribute("ProductId", new oracle.jbo.domain.Number(p_productId));      newUserComponentsRow.setAttribute("Component1", p_componentId);      newUserComponentsRow.setAttribute("SubComponent", p_subComponentId);    } catch (Exception e) {        e.printStackTrace();        return "Failure";    }        return "Success";  }Expose this method to client interface.To display the root node we need a custom VO which can be achieved using below query. SELECT Users.ACTIVE, Users.BUGDB_ID, Users.EMAIL, Users.FIRSTNAME, Users.GLOBAL_ID, Users.LASTNAME, Users.MANAGER_ID, Users.MANAGER_PRIVILEGEFROM USERS UsersWHERE Users.MANAGER_ID is NULLCreate VL between UsersView and UsersRootNodeView VOs.Drop ProductsView from DC as ADF Tree to jspx page.Add Tree Level Rule based on ComponentsView and SubComponentsView.Drop UsersRootNodeView as ADF Tree TableAdd Tree Level Rules based on UserComponentsView and UsersView.Add DragSource to ADF Tree and CollectionDropTarget to ADF Tree Table respectively.Bind CollectionDropTarget's DropTarget to backing bean and implement method of signature DnDAction (DropEvent), this method gets invoked when Tree Table encounters a drop action, here details required for creating new record are captured from the drag source and passed to 'createUserComponents' method. public DnDAction onTreeDrop(DropEvent dropEvent) {      String newBugdbId = "";      String msgtxt="";            try {          // Getting the target node bugdb id          Object serverRowKey = dropEvent.getDropSite();          if (serverRowKey != null) {                  //Code for Tree Table as target              String dropcomponent = dropEvent.getDropComponent().toString();              dropcomponent = (String)dropcomponent.subSequence(0, dropcomponent.indexOf("["));              if (dropcomponent.equals("RichTreeTable")){                RichTreeTable richTreeTable = (RichTreeTable)dropEvent.getDropComponent();                richTreeTable.setRowKey(serverRowKey);                int rowIndexTreeTable = richTreeTable.getRowIndex();                //Drop Target Logic                if (((JUCtrlHierNodeBinding)richTreeTable.getRowData(rowIndexTreeTable)).getAttributeValue()==null) {                  //Get Parent                  newBugdbId = (String)((JUCtrlHierNodeBinding)richTreeTable.getRowData(rowIndexTreeTable)).getParent().getAttributeValue();                } else {                  if (isNum(((JUCtrlHierNodeBinding)richTreeTable.getRowData(rowIndexTreeTable)).getAttributeValue().toString())) {                    //Get Parent's parent                              newBugdbId = (String)((JUCtrlHierNodeBinding)richTreeTable.getRowData(rowIndexTreeTable)).getParent().getParent().getAttributeValue();                  } else{                      //Dropped on USER                                          newBugdbId = (String)((JUCtrlHierNodeBinding)richTreeTable.getRowData(rowIndexTreeTable)).getAttributeValue();                  }                  }              }           }                     DataFlavor<RowKeySet> df = DataFlavor.getDataFlavor(RowKeySet.class);          RowKeySet droppedValue = dropEvent.getTransferable().getData(df);            Object[] keys = droppedValue.toArray();          Key componentKey = null;          Key subComponentKey = null;           // binding for createUserComponents method defined in AppModuleImpl class  to insert record in database.                      operationBinding = bindings.getOperationBinding("createUserComponents");            // get the Product, Component, Subcomponent details and insert to UserComponents table.          // loop through the keys if more than one comp/subcomponent is select.                   for (int i = 0; i < keys.length; i++) {                  System.out.println("in for :"+i);              List list = (List)keys[i];                  System.out.println("list "+i+" : "+list);              System.out.println("list size "+list.size());              if (list.size() == 1) {                                // we cannot drag and drop  the highest node !                                msgtxt="You cannot drop Products, please drop Component or SubComponent from the Tree.";                  System.out.println(msgtxt);                                this.showInfoMessage(msgtxt);              } else {                  if (list.size() == 2) {                    // were doing the first branch, in this case all components.                    componentKey = (Key)list.get(1);                    Object[] droppedProdCompValues = componentKey.getAttributeValues();                    operationBinding.getParamsMap().put("p_bugdbId",newBugdbId);                    operationBinding.getParamsMap().put("p_productId",droppedProdCompValues[0]);                    operationBinding.getParamsMap().put("p_componentId",droppedProdCompValues[1]);                    operationBinding.getParamsMap().put("p_subComponentId","ALL");                    Object result = operationBinding.execute();              } else {                    subComponentKey = (Key)list.get(2);                    Object[] droppedProdCompSubCompValues = subComponentKey.getAttributeValues();                    operationBinding.getParamsMap().put("p_bugdbId",newBugdbId);                    operationBinding.getParamsMap().put("p_productId",droppedProdCompSubCompValues[0]);                    operationBinding.getParamsMap().put("p_componentId",droppedProdCompSubCompValues[1]);                    operationBinding.getParamsMap().put("p_subComponentId",droppedProdCompSubCompValues[2]);                    Object result = operationBinding.execute();                  }                   }            }                        /* this.getCil1().setDisabled(false);            this.getCil1().setPartialSubmit(true); */                      return DnDAction.MOVE;        } catch (Exception ex) {          System.out.println("drop failed with : " + ex.getMessage());          ex.printStackTrace();                  /* this.getCil1().setDisabled(true); */          return DnDAction.NONE;          }    } Run jspx page and drop a Component or Subcomponent from Products Tree to UserComponents Tree Table.

    Read the article

  • Include weather information in ASP.Net site from weather.com services

    - by sreejukg
    In this article, I am going to demonstrate how you can use the XMLOAP services (referred as XOAP from here onwards) provided by weather.com to display the weather information in your website. The XOAP services are available to be used for free of charge, provided you are comply with requirements from weather.com. I am writing this article from a technical point of view. If you are planning to use weather.com XOAP services in your application, please refer to the terms and conditions from weather.com website. In order to start using the XOAP services, you need to sign up the XOAP datafeed. The signing process is simple, you simply browse the url http://www.weather.com/services/xmloap.html. The URL looks similar to the following. Click on the sign up button, you will reach the registration page. Here you need to specify the site name you need to use this feed for. The form looks similar to the following. Once you fill all the mandatory information, click on save and continue button. That’s it. The registration is over. You will receive an email that contains your partner id, license key and SDK. The SDK available in a zipped format, contains the terms of use and documentation about the services available. Other than this the SDK includes the logos and icons required to display the weather information. As per the SDK, currently there are 2 types of information available through XOAP. These services are Current Conditions for over 30,000 U.S. and over 7,900 international Location IDs Updated at least Hourly Five-Day Forecast (today + 4 additional forecast days in consecutive order beginning with tomorrow) for over 30,000 U.S. and over 7,900 international Location IDs Updated at least Three Times Daily The SDK provides detailed information about the fields included in response of each service. Additionally there is a refresh rate that you need to comply with. As per the SDK, the refresh rate means the following “Refresh Rate” shall mean the maximum frequency with which you may call the XML Feed for a given LocID requesting a data set for that LocID. During the time period in between refresh periods the data must be cached by you either in the memory on your servers or in Your Desktop Application. About the Services Weather.com will provide you with access to the XML Feed over the Internet through the hostname xoap.weather.com. The weather data from the XML feed must be requested for a specific location. So you need a location ID (LOC ID). The XML feed work with 2 types of location IDs. First one is with City Identifiers and second one is using 5 Digit US postal codes. If you do not know your location ID, don’t worry, there is a location id search service available for you to retrieve the location id from city name. Since I am a resident in the Kingdom of Bahrain, I am going to retrieve the weather information for Manama(the capital of Bahrain) . In order to get the location ID for Manama, type the following URL in your address bar. http://xoap.weather.com/search/search?where=manama I got the following XML output. <?xml version="1.0" encoding="UTF-8"?> <!-- This document is intended only for use by authorized licensees of The –> <!-- Weather Channel. Unauthorized use is prohibited. Copyright 1995-2011, –> <!-- The Weather Channel Interactive, Inc. All Rights Reserved. –> <search ver="3.0">       <loc id="BAXX0001" type="1">Al Manama, Bahrain</loc> </search> You can try this with any city name, if the city is available, it will return the location id, and otherwise, it will return nothing. In order to get the weather information, from XOAP,  you need to pass certain parameters to the XOAP service. A brief about the parameters are as follows. Please refer SDK for more details. Parameter name Possible Value cc Optional, if you include this, the current condition will be returned. Value can be anything, as it will be ignored e.g. cc=* dayf If you want the forecast for 5 days, specify dayf=5 This is optional iink Value should be XOAP par Your partner id. You can find this in your registration email from weather.com prod Value should be XOAP key The license key assigned to you. This will be available in the registration email unit s or m (standard or matric or you can think of Celsius/Fahrenheit) this is optional field, if not specified the unit will be standard(s) The URL host for the XOAP service is http://xoap.weather.com. So for my purpose, I need the following request to be made to access the XOAP services. http://xoap.weather.com/weather/local/BAXX0001?cc=*&link=xoap&prod=xoap&par=*********&key=************** (The ***** to be replaced with the corresponding alternatives) The response XML have a root element “weather”. Under the root element, it has the following sections <head> - the meta data information about the weather results returned. <loc> - the location data block that provides, the information about the location for which the wheather data is retrieved. <lnks> - the 4 promotional links you need to place along with the weather display. Additional to these 4 links, there should be another link with weather channel logo to the home page of weather.com. <cc> - the current condition data. This element will be there only if you specify the cc element in the request. <dayf> - the forcast data as you specified. This element will be there only if you specify the dayf in the request. In this walkthrough, I am going to capture the weather information for Manama (Location ID: BAXX0001). You need 2 applications to display weather information in your website. A Console application that retrieves data from the XMLOAP and store in the SQL Server database (or any data store as you prefer).This application will be scheduled to execute in every 25 minutes using windows task scheduler, so that we can comply with the refresh rate. A web application that display data from the SQL Server database Retrieve the Weather from XOAP I have created a console application named, Weather Service. I created a SQL server database, with the following columns. I named the table as tblweather. You are free to choose any name. Column name Description lastUpdated Datetime, this is the last time when the weather data is updated. This is the time of the service running TemparatureDateTime The date and time returned by XML feed Temparature The temperature returned by the XML feed. TemparatureUnit The unit of the temperature returned by the XML feed iconId The id of the icon to be used. Currently 48 icons from 0 to 47 are available. WeatherDescription The Weather Description Phrase returned by the feed. Link1url The url to the first promo link Link1Text The text for the first promo link Link2url The url to the second promo link Link2Text The text for the second promo link Link3url The url to the third promo link Link3Text The text for the third promo link Link4url The url to the fourth promo link Link4Text The text for the fourth promo link Every time when the service runs, the application will update the database columns from the XOAP data feed. When the application starts, It is going to get the data as XML from the url. This demonstration uses LINQ to extract the necessary data from the fetched XML. The following are the code segment for extracting data from the weather XML using LINQ. // first, create an instance of the XDocument class with the XOAP URL. replace **** with the corresponding values. XDocument weather = XDocument.Load("http://xoap.weather.com/weather/local/BAXX0001?cc=*&link=xoap&prod=xoap&par=***********&key=c*********"); // construct a query using LINQ var feedResult = from item in weather.Descendants() select new { unit = item.Element("head").Element("ut").Value, temp = item.Element("cc").Element("tmp").Value, tempDate = item.Element("cc").Element("lsup").Value, iconId = item.Element("cc").Element("icon").Value, description = item.Element("cc").Element("t").Value, links = from link in item.Elements("lnks").Elements("link") select new { url = link.Element("l").Value, text = link.Element("t").Value } }; // Load the root node to a variable, you may use foreach construct instead. var item1 = feedResult.First(); *If you want to learn more about LINQ and XML, read this nice blog from Scott GU. http://weblogs.asp.net/scottgu/archive/2007/08/07/using-linq-to-xml-and-how-to-build-a-custom-rss-feed-reader-with-it.aspx Now you have all the required values in item1. For e.g. if you want to get the temperature, use item1.temp; Now I just need to execute an SQL query against the database. See the connection part. using (SqlConnection conn = new SqlConnection(@"Data Source=sreeju\sqlexpress;Initial Catalog=Sample;Integrated Security=True")) { string strSql = @"update tblweather set lastupdated=getdate(), temparatureDateTime = @temparatureDateTime, temparature=@temparature, temparatureUnit=@temparatureUnit, iconId = @iconId, description=@description, link1url=@link1url, link1text=@link1text, link2url=@link2url, link2text=@link2text,link3url=@link3url, link3text=@link3text,link4url=@link4url, link4text=@link4text"; SqlCommand comm = new SqlCommand(strSql, conn); comm.Parameters.AddWithValue("temparatureDateTime", item1.tempDate); comm.Parameters.AddWithValue("temparature", item1.temp); comm.Parameters.AddWithValue("temparatureUnit", item1.unit); comm.Parameters.AddWithValue("description", item1.description); comm.Parameters.AddWithValue("iconId", item1.iconId); var lstLinks = item1.links; comm.Parameters.AddWithValue("link1url", lstLinks.ElementAt(0).url); comm.Parameters.AddWithValue("link1text", lstLinks.ElementAt(0).text); comm.Parameters.AddWithValue("link2url", lstLinks.ElementAt(1).url); comm.Parameters.AddWithValue("link2text", lstLinks.ElementAt(1).text); comm.Parameters.AddWithValue("link3url", lstLinks.ElementAt(2).url); comm.Parameters.AddWithValue("link3text", lstLinks.ElementAt(2).text); comm.Parameters.AddWithValue("link4url", lstLinks.ElementAt(3).url); comm.Parameters.AddWithValue("link4text", lstLinks.ElementAt(3).text); conn.Open(); comm.ExecuteNonQuery(); conn.Close(); Console.WriteLine("database updated"); } Now click ctrl + f5 to run the service. I got the following output Check your database and make sure, the data is updated with the latest information from the service. (Make sure you inserted one row in the database by entering some values before executing the service. Otherwise you need to modify your application code to count the rows and conditionally perform insert/update query) Display the Weather information in ASP.Net page Now you got all the data in the database. You just need to create a web application and display the data from the database. I created a new ASP.Net web application with a default.aspx page. In order to comply with the terms of weather.com, You need to use Weather.com logo along with the weather display. You can find the necessary logos to use under the folder “logos” in the SDK. Additionally copy any of the icon set from the folder “icons” to your web application. I used the 93x93 icon set. You are free to use any other sizes available. The design view of the page in VS2010 looks similar to the following. The page contains a heading, an image control (for displaying the weather icon), 2 label controls (for displaying temperature and weather description), 4 hyperlinks (for displaying the 4 promo links returned by the XOAP service) and weather.com logo with hyperlink to the weather.com home page. I am going to write code that will update the values of these controls from the values stored in the database by the service application as mentioned in the previous step. Go to the code behind file for the webpage, enter the following code under Page_Load event handler. using (SqlConnection conn = new SqlConnection(@"Data Source=sreeju\sqlexpress;Initial Catalog=Sample;Integrated Security=True")) { SqlCommand comm = new SqlCommand("select top 1 * from tblweather", conn); conn.Open(); SqlDataReader reader = comm.ExecuteReader(); if (reader.Read()) { lblTemparature.Text = reader["temparature"].ToString() + "&deg;" + reader["temparatureUnit"].ToString(); lblWeatherDescription.Text = reader["description"].ToString(); imgWeather.ImageUrl = "icons/" + reader["iconId"].ToString() + ".png"; lnk1.Text = reader["link1text"].ToString(); lnk1.NavigateUrl = reader["link1url"].ToString(); lnk2.Text = reader["link2text"].ToString(); lnk2.NavigateUrl = reader["link2url"].ToString(); lnk3.Text = reader["link3text"].ToString(); lnk3.NavigateUrl = reader["link3url"].ToString(); lnk4.Text = reader["link4text"].ToString(); lnk4.NavigateUrl = reader["link4url"].ToString(); } conn.Close(); } Press ctrl + f5 to run the page. You will see the following output. That’s it. You need to configure the console application to run every 25 minutes so that the database is updated. Also you can fetch the forecast information and store those in the database, and then retrieve it later in your web page. Since the data resides in your database, you have the full control over your display. You need to make sure your website comply with weather.com license requirements. If you want to get the source code of this walkthrough through the application, post your email address below. Hope you enjoy the reading.

    Read the article

  • JMS Step 2 - Using the QueueSend.java Sample Program to Send a Message to a JMS Queue

    - by John-Brown.Evans
    JMS Step 2 - Using the QueueSend.java Sample Program to Send a Message to a JMS Queue .c21_2{vertical-align:top;width:487.3pt;border-style:solid;border-color:#000000;border-width:1pt;padding:5pt 5pt 5pt 5pt} .c15_2{vertical-align:top;width:487.3pt;border-style:solid;border-color:#ffffff;border-width:1pt;padding:5pt 5pt 5pt 5pt} .c0_2{padding-left:0pt;direction:ltr;margin-left:36pt} .c20_2{list-style-type:circle;margin:0;padding:0} .c10_2{list-style-type:disc;margin:0;padding:0} .c6_2{background-color:#ffffff} .c17_2{padding-left:0pt;margin-left:72pt} .c3_2{line-height:1.0;direction:ltr} .c1_2{font-size:10pt;font-family:"Courier New"} .c16_2{color:#1155cc;text-decoration:underline} .c13_2{color:inherit;text-decoration:inherit} .c7_2{background-color:#ffff00} .c9_2{border-collapse:collapse} .c2_2{font-family:"Courier New"} .c18_2{font-size:18pt} .c5_2{font-weight:bold} .c19_2{color:#ff0000} .c12_2{background-color:#f3f3f3;border-style:solid;border-color:#000000;border-width:1pt;} .c14_2{font-size:24pt} .c8_2{direction:ltr;background-color:#ffffff} .c11_2{font-style:italic} .c4_2{height:11pt} .title{padding-top:24pt;line-height:1.15;text-align:left;color:#000000;font-size:36pt;font-family:"Arial";font-weight:bold;padding-bottom:6pt}.subtitle{padding-top:18pt;line-height:1.15;text-align:left;color:#666666;font-style:italic;font-size:24pt;font-family:"Georgia";padding-bottom:4pt} li{color:#000000;font-size:10pt;font-family:"Arial"} p{color:#000000;font-size:10pt;margin:0;font-family:"Arial"} h1{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:24pt;font-family:"Arial";font-weight:normal;padding-bottom:0pt} h2{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:18pt;font-family:"Arial";font-weight:normal;padding-bottom:0pt} h3{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:14pt;font-family:"Arial";font-weight:normal;padding-bottom:0pt} h4{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:12pt;font-family:"Arial";font-weight:normal;padding-bottom:0pt} h5{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:11pt;font-family:"Arial";font-weight:normal;padding-bottom:0pt} h6{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:10pt;font-family:"Arial";font-weight:normal;padding-bottom:0pt} This post is the second in a series of JMS articles which demonstrate how to use JMS queues in a SOA context. In the previous post JMS Step 1 - How to Create a Simple JMS Queue in Weblogic Server 11g I showed you how to create a JMS queue and its dependent objects in WebLogic Server. In this article, we will use a sample program to write a message to that queue. Please review the previous post if you have not created those objects yet, as they will be required later in this example. The previous post also includes useful background information and links to the Oracle documentation for addional research. The following post in this series will show how to read the message from the queue again. 1. Source code The following java code will be used to write a message to the JMS queue. It is based on a sample program provided with the WebLogic Server installation. The sample is not installed by default, but needs to be installed manually using the WebLogic Server Custom Installation option, together with many, other useful samples. You can either copy-paste the following code into your editor, or install all the samples. The knowledge base article in My Oracle Support: How To Install WebLogic Server and JMS Samples in WLS 10.3.x (Doc ID 1499719.1) describes how to install the samples. QueueSend.java package examples.jms.queue; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.util.Hashtable; import javax.jms.*; import javax.naming.Context; import javax.naming.InitialContext; import javax.naming.NamingException; /** This example shows how to establish a connection * and send messages to the JMS queue. The classes in this * package operate on the same JMS queue. Run the classes together to * witness messages being sent and received, and to browse the queue * for messages. The class is used to send messages to the queue. * * @author Copyright (c) 1999-2005 by BEA Systems, Inc. All Rights Reserved. */ public class QueueSend { // Defines the JNDI context factory. public final static String JNDI_FACTORY="weblogic.jndi.WLInitialContextFactory"; // Defines the JMS context factory. public final static String JMS_FACTORY="jms/TestConnectionFactory"; // Defines the queue. public final static String QUEUE="jms/TestJMSQueue"; private QueueConnectionFactory qconFactory; private QueueConnection qcon; private QueueSession qsession; private QueueSender qsender; private Queue queue; private TextMessage msg; /** * Creates all the necessary objects for sending * messages to a JMS queue. * * @param ctx JNDI initial context * @param queueName name of queue * @exception NamingException if operation cannot be performed * @exception JMSException if JMS fails to initialize due to internal error */ public void init(Context ctx, String queueName) throws NamingException, JMSException { qconFactory = (QueueConnectionFactory) ctx.lookup(JMS_FACTORY); qcon = qconFactory.createQueueConnection(); qsession = qcon.createQueueSession(false, Session.AUTO_ACKNOWLEDGE); queue = (Queue) ctx.lookup(queueName); qsender = qsession.createSender(queue); msg = qsession.createTextMessage(); qcon.start(); } /** * Sends a message to a JMS queue. * * @param message message to be sent * @exception JMSException if JMS fails to send message due to internal error */ public void send(String message) throws JMSException { msg.setText(message); qsender.send(msg); } /** * Closes JMS objects. * @exception JMSException if JMS fails to close objects due to internal error */ public void close() throws JMSException { qsender.close(); qsession.close(); qcon.close(); } /** main() method. * * @param args WebLogic Server URL * @exception Exception if operation fails */ public static void main(String[] args) throws Exception { if (args.length != 1) { System.out.println("Usage: java examples.jms.queue.QueueSend WebLogicURL"); return; } InitialContext ic = getInitialContext(args[0]); QueueSend qs = new QueueSend(); qs.init(ic, QUEUE); readAndSend(qs); qs.close(); } private static void readAndSend(QueueSend qs) throws IOException, JMSException { BufferedReader msgStream = new BufferedReader(new InputStreamReader(System.in)); String line=null; boolean quitNow = false; do { System.out.print("Enter message (\"quit\" to quit): \n"); line = msgStream.readLine(); if (line != null && line.trim().length() != 0) { qs.send(line); System.out.println("JMS Message Sent: "+line+"\n"); quitNow = line.equalsIgnoreCase("quit"); } } while (! quitNow); } private static InitialContext getInitialContext(String url) throws NamingException { Hashtable env = new Hashtable(); env.put(Context.INITIAL_CONTEXT_FACTORY, JNDI_FACTORY); env.put(Context.PROVIDER_URL, url); return new InitialContext(env); } } 2. How to Use This Class 2.1 From the file system on UNIX/Linux Log in to a machine with a WebLogic installation and create a directory to contain the source and code matching the package name, e.g. $HOME/examples/jms/queue. Copy the above QueueSend.java file to this directory. Set the CLASSPATH and environment to match the WebLogic server environment. Go to $MIDDLEWARE_HOME/user_projects/domains/base_domain/bin  and execute . ./setDomainEnv.sh Collect the following information required to run the script: The JNDI name of a JMS queue to use In the Weblogic server console > Services > Messaging > JMS Modules > (Module name, e.g. TestJMSModule) > (JMS queue name, e.g. TestJMSQueue)Select the queue and note its JNDI name, e.g. jms/TestJMSQueue The JNDI name of a connection factory to connect to the queue Follow the same path as above to get the connection factory for the above queue, e.g. TestConnectionFactory and its JNDI namee.g. jms/TestConnectionFactory The URL and port of the WebLogic server running the above queue Check the JMS server for the above queue and the managed server it is targeted to, for example soa_server1. Now find the port this managed server is listening on, by looking at its entry under Environment > Servers in the WLS console, e.g. 8001 The URL for the server to be given to the QueueSend program in this example will therefore be t3://host.domain:8001 e.g. t3://jbevans-lx.de.oracle.com:8001 Edit QueueSend.java and enter the above queue name and connection factory respectively under ...public final static String  JMS_FACTORY=" jms/TestConnectionFactory "; ... public final static String QUEUE=" jms/TestJMSQueue "; ... Compile QueueSend.java using javac QueueSend.java Go to the source’s top-level directory and execute it using java examples.jms.queue.QueueSend t3://jbevans-lx.de.oracle.com:8001 This will prompt for a text input or “quit” to end. In the WLS console, go to the queue and select Monitoring to confirm that a new message was written to the queue. 2.2 From JDeveloper Create a new application in JDeveloper, called, for example JMSTests. When prompted for a project name, enter QueueSend and select Java as the technology Default Package = examples.jms.queue (but you can enter anything here as you will overwrite it in the code later). Leave the other values at their defaults. Press Finish Create a new Java class called QueueSend and use the default values This will create a file called QueueSend.java. Open QueueSend.java, if it is not already open and replace all its contents with the QueueSend java code listed above Some lines might have warnings due to unfound objects. These are due to missing libraries in the JDeveloper project. Add the following libraries to the JDeveloper project: right-click the QueueSend  project in the navigation menu and select Libraries and Classpath , then Add JAR/Directory  Go to the folder containing the JDeveloper installation and find/choose the file javax.jms_1.1.1.jar , e.g. at D:\oracle\jdev11116\modules\javax.jms_1.1.1.jar Do the same for the weblogic.jar file located, for example in D:\oracle\jdev11116\wlserver_10.3\server\lib\weblogic.jar Now you should be able to compile the project, for example by selecting the Make or Rebuild icons   If you try to execute the project, you will get a usage message, as it requires a parameter pointing to the WLS installation containing the JMS queue, for example t3://jbevans-lx.de.oracle.com:8001 . You can automatically pass this parameter to the program from JDeveloper by editing the project’s Run/Debug/Profile. Select the project properties, select Run/Debug/Profile and edit the Default run configuration and add the connection parameter to the Program Arguments field If you execute it again, you will see that it has passed the parameter to the start command If you get a ClassNotFoundException for the class weblogic.jndi.WLInitialContextFactory , then check that the weblogic.jar file was correctly added to the project in one of the earlier steps above. Set the values of JMS_FACTORY and QUEUE the same way as described above in the description of how to use this from a Linux file system, i.e. ...public final static String  JMS_FACTORY=" jms/TestConnectionFactory "; ... public final static String QUEUE=" jms/TestJMSQueue "; ... You need to make one more change to the project. If you execute it now, it will prompt for the payload for the JMS message, but you won’t be able to enter it by default in JDeveloper. You need to enable program input for the project first. Select the project’s properties, then Tool Settings, then check the Allow Program Input checkbox at the bottom and Save. Now when you execute the project, you will get a text entry field at the bottom into which you can enter the payload. You can enter multiple messages until you enter “quit”, which will cause the program to stop. The following screen shot shows the TestJMSQueue’s Monitoring page, after a message was sent to the queue: This concludes the sample. In the following post I will show you how to read the message from the queue again.

    Read the article

  • Dynamically loading Assemblies to reduce Runtime Depencies

    - by Rick Strahl
    I've been working on a request to the West Wind Application Configuration library to add JSON support. The config library is a very easy to use code-first approach to configuration: You create a class that holds the configuration data that inherits from a base configuration class, and then assign a persistence provider at runtime that determines where and how the configuration data is store. Currently the library supports .NET Configuration stores (web.config/app.config), XML files, SQL records and string storage.About once a week somebody asks me about JSON support and I've deflected this question for the longest time because frankly I think that JSON as a configuration store doesn't really buy a heck of a lot over XML. Both formats require the user to perform some fixup of the plain configuration data - in XML into XML tags, with JSON using JSON delimiters for properties and property formatting rules. Sure JSON is a little less verbose and maybe a little easier to read if you have hierarchical data, but overall the differences are pretty minor in my opinion. And yet - the requests keep rolling in.Hard Link Issues in a Component LibraryAnother reason I've been hesitant is that I really didn't want to pull in a dependency on an external JSON library - in this case JSON.NET - into the core library. If you're not using JSON.NET elsewhere I don't want a user to have to require a hard dependency on JSON.NET unless they want to use the JSON feature. JSON.NET is also sensitive to versions and doesn't play nice with multiple versions when hard linked. For example, when you have a reference to V4.4 in your project but the host application has a reference to version 4.5 you can run into assembly load problems. NuGet's Update-Package can solve some of this *if* you can recompile, but that's not ideal for a component that's supposed to be just plug and play. This is no criticism of JSON.NET - this really applies to any dependency that might change.  So hard linking the DLL can be problematic for a number reasons, but the primary reason is to not force loading of JSON.NET unless you actually need it when you use the JSON configuration features of the library.Enter Dynamic LoadingSo rather than adding an assembly reference to the project, I decided that it would be better to dynamically load the DLL at runtime and then use dynamic typing to access various classes. This allows me to run without a hard assembly reference and allows more flexibility with version number differences now and in the future.But there are also a couple of downsides:No assembly reference means only dynamic access - no compiler type checking or IntellisenseRequirement for the host application to have reference to JSON.NET or else get runtime errorsThe former is minor, but the latter can be problematic. Runtime errors are always painful, but in this case I'm willing to live with this. If you want to use JSON configuration settings JSON.NET needs to be loaded in the project. If this is a Web project, it'll likely be there already.So there are a few things that are needed to make this work:Dynamically create an instance and optionally attempt to load an Assembly (if not loaded)Load types into dynamic variablesUse Reflection for a few tasks like statics/enumsThe dynamic keyword in C# makes the formerly most difficult Reflection part - method calls and property assignments - fairly painless. But as cool as dynamic is it doesn't handle all aspects of Reflection. Specifically it doesn't deal with object activation, truly dynamic (string based) member activation or accessing of non instance members, so there's still a little bit of work left to do with Reflection.Dynamic Object InstantiationThe first step in getting the process rolling is to instantiate the type you need to work with. This might be a two step process - loading the instance from a string value, since we don't have a hard type reference and potentially having to load the assembly. Although the host project might have a reference to JSON.NET, that instance might have not been loaded yet since it hasn't been accessed yet. In ASP.NET this won't be a problem, since ASP.NET preloads all referenced assemblies on AppDomain startup, but in other executable project, assemblies are just in time loaded only when they are accessed.Instantiating a type is a two step process: Finding the type reference and then activating it. Here's the generic code out of my ReflectionUtils library I use for this:/// <summary> /// Creates an instance of a type based on a string. Assumes that the type's /// </summary> /// <param name="typeName">Common name of the type</param> /// <param name="args">Any constructor parameters</param> /// <returns></returns> public static object CreateInstanceFromString(string typeName, params object[] args) { object instance = null; Type type = null; try { type = GetTypeFromName(typeName); if (type == null) return null; instance = Activator.CreateInstance(type, args); } catch { return null; } return instance; } /// <summary> /// Helper routine that looks up a type name and tries to retrieve the /// full type reference in the actively executing assemblies. /// </summary> /// <param name="typeName"></param> /// <returns></returns> public static Type GetTypeFromName(string typeName) { Type type = null; // Let default name binding find it type = Type.GetType(typeName, false); if (type != null) return type; // look through assembly list var assemblies = AppDomain.CurrentDomain.GetAssemblies(); // try to find manually foreach (Assembly asm in assemblies) { type = asm.GetType(typeName, false); if (type != null) break; } return type; } To use this for loading JSON.NET I have a small factory function that instantiates JSON.NET and sets a bunch of configuration settings on the generated object. The startup code also looks for failure and tries loading up the assembly when it fails since that's the main reason the load would fail. Finally it also caches the loaded instance for reuse (according to James the JSON.NET instance is thread safe and quite a bit faster when cached). Here's what the factory function looks like in JsonSerializationUtils:/// <summary> /// Dynamically creates an instance of JSON.NET /// </summary> /// <param name="throwExceptions">If true throws exceptions otherwise returns null</param> /// <returns>Dynamic JsonSerializer instance</returns> public static dynamic CreateJsonNet(bool throwExceptions = true) { if (JsonNet != null) return JsonNet; lock (SyncLock) { if (JsonNet != null) return JsonNet; // Try to create instance dynamic json = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.JsonSerializer"); if (json == null) { try { var ass = AppDomain.CurrentDomain.Load("Newtonsoft.Json"); json = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.JsonSerializer"); } catch (Exception ex) { if (throwExceptions) throw; return null; } } if (json == null) return null; json.ReferenceLoopHandling = (dynamic) ReflectionUtils.GetStaticProperty("Newtonsoft.Json.ReferenceLoopHandling", "Ignore"); // Enums as strings in JSON dynamic enumConverter = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.Converters.StringEnumConverter"); json.Converters.Add(enumConverter); JsonNet = json; } return JsonNet; }This code's purpose is to return a fully configured JsonSerializer instance. As you can see the code tries to create an instance and when it fails tries to load the assembly, and then re-tries loading.Once the instance is loaded some configuration occurs on it. Specifically I set the ReferenceLoopHandling option to not blow up immediately when circular references are encountered. There are a host of other small config setting that might be useful to set, but the default seem to be good enough in recent versions. Note that I'm setting ReferenceLoopHandling which requires an Enum value to be set. There's no real easy way (short of using the cardinal numeric value) to set a property or pass parameters from static values or enums. This means I still need to use Reflection to make this work. I'm using the same ReflectionUtils class I previously used to handle this for me. The function looks up the type and then uses Type.InvokeMember() to read the static property.Another feature I need is have Enum values serialized as strings rather than numeric values which is the default. To do this I can use the StringEnumConverter to convert enums to strings by adding it to the Converters collection.As you can see there's still a bit of Reflection to be done even in C# 4+ with dynamic, but with a few helpers this process is relatively painless.Doing the actual JSON ConversionFinally I need to actually do my JSON conversions. For the Utility class I need serialization that works for both strings and files so I created four methods that handle these tasks two each for serialization and deserialization for string and file.Here's what the File Serialization looks like:/// <summary> /// Serializes an object instance to a JSON file. /// </summary> /// <param name="value">the value to serialize</param> /// <param name="fileName">Full path to the file to write out with JSON.</param> /// <param name="throwExceptions">Determines whether exceptions are thrown or false is returned</param> /// <param name="formatJsonOutput">if true pretty-formats the JSON with line breaks</param> /// <returns>true or false</returns> public static bool SerializeToFile(object value, string fileName, bool throwExceptions = false, bool formatJsonOutput = false) { dynamic writer = null; FileStream fs = null; try { Type type = value.GetType(); var json = CreateJsonNet(throwExceptions); if (json == null) return false; fs = new FileStream(fileName, FileMode.Create); var sw = new StreamWriter(fs, Encoding.UTF8); writer = Activator.CreateInstance(JsonTextWriterType, sw); if (formatJsonOutput) writer.Formatting = (dynamic)Enum.Parse(FormattingType, "Indented"); writer.QuoteChar = '"'; json.Serialize(writer, value); } catch (Exception ex) { Debug.WriteLine("JsonSerializer Serialize error: " + ex.Message); if (throwExceptions) throw; return false; } finally { if (writer != null) writer.Close(); if (fs != null) fs.Close(); } return true; }You can see more of the dynamic invocation in this code. First I grab the dynamic JsonSerializer instance using the CreateJsonNet() method shown earlier which returns a dynamic. I then create a JsonTextWriter and configure a couple of enum settings on it, and then call Serialize() on the serializer instance with the JsonTextWriter that writes the output to disk. Although this code is dynamic it's still fairly short and readable.For full circle operation here's the DeserializeFromFile() version:/// <summary> /// Deserializes an object from file and returns a reference. /// </summary> /// <param name="fileName">name of the file to serialize to</param> /// <param name="objectType">The Type of the object. Use typeof(yourobject class)</param> /// <param name="binarySerialization">determines whether we use Xml or Binary serialization</param> /// <param name="throwExceptions">determines whether failure will throw rather than return null on failure</param> /// <returns>Instance of the deserialized object or null. Must be cast to your object type</returns> public static object DeserializeFromFile(string fileName, Type objectType, bool throwExceptions = false) { dynamic json = CreateJsonNet(throwExceptions); if (json == null) return null; object result = null; dynamic reader = null; FileStream fs = null; try { fs = new FileStream(fileName, FileMode.Open, FileAccess.Read); var sr = new StreamReader(fs, Encoding.UTF8); reader = Activator.CreateInstance(JsonTextReaderType, sr); result = json.Deserialize(reader, objectType); reader.Close(); } catch (Exception ex) { Debug.WriteLine("JsonNetSerialization Deserialization Error: " + ex.Message); if (throwExceptions) throw; return null; } finally { if (reader != null) reader.Close(); if (fs != null) fs.Close(); } return result; }This code is a little more compact since there are no prettifying options to set. Here JsonTextReader is created dynamically and it receives the output from the Deserialize() operation on the serializer.You can take a look at the full JsonSerializationUtils.cs file on GitHub to see the rest of the operations, but the string operations are very similar - the code is fairly repetitive.These generic serialization utilities isolate the dynamic serialization logic that has to deal with the dynamic nature of JSON.NET, and any code that uses these functions is none the wiser that JSON.NET is dynamically loaded.Using the JsonSerializationUtils WrapperThe final consumer of the SerializationUtils wrapper is an actual ConfigurationProvider, that is responsible for handling reading and writing JSON values to and from files. The provider is simple a small wrapper around the SerializationUtils component and there's very little code to make this work now:The whole provider looks like this:/// <summary> /// Reads and Writes configuration settings in .NET config files and /// sections. Allows reading and writing to default or external files /// and specification of the configuration section that settings are /// applied to. /// </summary> public class JsonFileConfigurationProvider<TAppConfiguration> : ConfigurationProviderBase<TAppConfiguration> where TAppConfiguration: AppConfiguration, new() { /// <summary> /// Optional - the Configuration file where configuration settings are /// stored in. If not specified uses the default Configuration Manager /// and its default store. /// </summary> public string JsonConfigurationFile { get { return _JsonConfigurationFile; } set { _JsonConfigurationFile = value; } } private string _JsonConfigurationFile = string.Empty; public override bool Read(AppConfiguration config) { var newConfig = JsonSerializationUtils.DeserializeFromFile(JsonConfigurationFile, typeof(TAppConfiguration)) as TAppConfiguration; if (newConfig == null) { if(Write(config)) return true; return false; } DecryptFields(newConfig); DataUtils.CopyObjectData(newConfig, config, "Provider,ErrorMessage"); return true; } /// <summary> /// Return /// </summary> /// <typeparam name="TAppConfig"></typeparam> /// <returns></returns> public override TAppConfig Read<TAppConfig>() { var result = JsonSerializationUtils.DeserializeFromFile(JsonConfigurationFile, typeof(TAppConfig)) as TAppConfig; if (result != null) DecryptFields(result); return result; } /// <summary> /// Write configuration to XmlConfigurationFile location /// </summary> /// <param name="config"></param> /// <returns></returns> public override bool Write(AppConfiguration config) { EncryptFields(config); bool result = JsonSerializationUtils.SerializeToFile(config, JsonConfigurationFile,false,true); // Have to decrypt again to make sure the properties are readable afterwards DecryptFields(config); return result; } }This incidentally demonstrates how easy it is to create a new provider for the West Wind Application Configuration component. Simply implementing 3 methods will do in most cases.Note this code doesn't have any dynamic dependencies - all that's abstracted away in the JsonSerializationUtils(). From here on, serializing JSON is just a matter of calling the static methods on the SerializationUtils class.Already, there are several other places in some other tools where I use JSON serialization this is coming in very handy. With a couple of lines of code I was able to add JSON.NET support to an older AJAX library that I use replacing quite a bit of code that was previously in use. And for any other manual JSON operations (in a couple of apps I use JSON Serialization for 'blob' like document storage) this is also going to be handy.Performance?Some of you might be thinking that using dynamic and Reflection can't be good for performance. And you'd be right… In performing some informal testing it looks like the performance of the native code is nearly twice as fast as the dynamic code. Most of the slowness is attributable to type lookups. To test I created a native class that uses an actual reference to JSON.NET and performance was consistently around 85-90% faster with the referenced code. That being said though - I serialized 10,000 objects in 80ms vs. 45ms so this isn't hardly slouchy. For the configuration component speed is not that important because both read and write operations typically happen once on first access and then every once in a while. But for other operations - say a serializer trying to handle AJAX requests on a Web Server one would be well served to create a hard dependency.Dynamic Loading - Worth it?On occasion dynamic loading makes sense. But there's a price to be paid in added code complexity and a performance hit. But for some operations that are not pivotal to a component or application and only used under certain circumstances dynamic loading can be beneficial to avoid having to ship extra files and loading down distributions. These days when you create new projects in Visual Studio with 30 assemblies before you even add your own code, trying to keep file counts under control seems a good idea. It's not the kind of thing you do on a regular basis, but when needed it can be a useful tool. Hopefully some of you find this information useful…© Rick Strahl, West Wind Technologies, 2005-2013Posted in .NET  C#   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

    Read the article

  • Dynamically loading Assemblies to reduce Runtime Dependencies

    - by Rick Strahl
    I've been working on a request to the West Wind Application Configuration library to add JSON support. The config library is a very easy to use code-first approach to configuration: You create a class that holds the configuration data that inherits from a base configuration class, and then assign a persistence provider at runtime that determines where and how the configuration data is store. Currently the library supports .NET Configuration stores (web.config/app.config), XML files, SQL records and string storage.About once a week somebody asks me about JSON support and I've deflected this question for the longest time because frankly I think that JSON as a configuration store doesn't really buy a heck of a lot over XML. Both formats require the user to perform some fixup of the plain configuration data - in XML into XML tags, with JSON using JSON delimiters for properties and property formatting rules. Sure JSON is a little less verbose and maybe a little easier to read if you have hierarchical data, but overall the differences are pretty minor in my opinion. And yet - the requests keep rolling in.Hard Link Issues in a Component LibraryAnother reason I've been hesitant is that I really didn't want to pull in a dependency on an external JSON library - in this case JSON.NET - into the core library. If you're not using JSON.NET elsewhere I don't want a user to have to require a hard dependency on JSON.NET unless they want to use the JSON feature. JSON.NET is also sensitive to versions and doesn't play nice with multiple versions when hard linked. For example, when you have a reference to V4.4 in your project but the host application has a reference to version 4.5 you can run into assembly load problems. NuGet's Update-Package can solve some of this *if* you can recompile, but that's not ideal for a component that's supposed to be just plug and play. This is no criticism of JSON.NET - this really applies to any dependency that might change.  So hard linking the DLL can be problematic for a number reasons, but the primary reason is to not force loading of JSON.NET unless you actually need it when you use the JSON configuration features of the library.Enter Dynamic LoadingSo rather than adding an assembly reference to the project, I decided that it would be better to dynamically load the DLL at runtime and then use dynamic typing to access various classes. This allows me to run without a hard assembly reference and allows more flexibility with version number differences now and in the future.But there are also a couple of downsides:No assembly reference means only dynamic access - no compiler type checking or IntellisenseRequirement for the host application to have reference to JSON.NET or else get runtime errorsThe former is minor, but the latter can be problematic. Runtime errors are always painful, but in this case I'm willing to live with this. If you want to use JSON configuration settings JSON.NET needs to be loaded in the project. If this is a Web project, it'll likely be there already.So there are a few things that are needed to make this work:Dynamically create an instance and optionally attempt to load an Assembly (if not loaded)Load types into dynamic variablesUse Reflection for a few tasks like statics/enumsThe dynamic keyword in C# makes the formerly most difficult Reflection part - method calls and property assignments - fairly painless. But as cool as dynamic is it doesn't handle all aspects of Reflection. Specifically it doesn't deal with object activation, truly dynamic (string based) member activation or accessing of non instance members, so there's still a little bit of work left to do with Reflection.Dynamic Object InstantiationThe first step in getting the process rolling is to instantiate the type you need to work with. This might be a two step process - loading the instance from a string value, since we don't have a hard type reference and potentially having to load the assembly. Although the host project might have a reference to JSON.NET, that instance might have not been loaded yet since it hasn't been accessed yet. In ASP.NET this won't be a problem, since ASP.NET preloads all referenced assemblies on AppDomain startup, but in other executable project, assemblies are just in time loaded only when they are accessed.Instantiating a type is a two step process: Finding the type reference and then activating it. Here's the generic code out of my ReflectionUtils library I use for this:/// <summary> /// Creates an instance of a type based on a string. Assumes that the type's /// </summary> /// <param name="typeName">Common name of the type</param> /// <param name="args">Any constructor parameters</param> /// <returns></returns> public static object CreateInstanceFromString(string typeName, params object[] args) { object instance = null; Type type = null; try { type = GetTypeFromName(typeName); if (type == null) return null; instance = Activator.CreateInstance(type, args); } catch { return null; } return instance; } /// <summary> /// Helper routine that looks up a type name and tries to retrieve the /// full type reference in the actively executing assemblies. /// </summary> /// <param name="typeName"></param> /// <returns></returns> public static Type GetTypeFromName(string typeName) { Type type = null; // Let default name binding find it type = Type.GetType(typeName, false); if (type != null) return type; // look through assembly list var assemblies = AppDomain.CurrentDomain.GetAssemblies(); // try to find manually foreach (Assembly asm in assemblies) { type = asm.GetType(typeName, false); if (type != null) break; } return type; } To use this for loading JSON.NET I have a small factory function that instantiates JSON.NET and sets a bunch of configuration settings on the generated object. The startup code also looks for failure and tries loading up the assembly when it fails since that's the main reason the load would fail. Finally it also caches the loaded instance for reuse (according to James the JSON.NET instance is thread safe and quite a bit faster when cached). Here's what the factory function looks like in JsonSerializationUtils:/// <summary> /// Dynamically creates an instance of JSON.NET /// </summary> /// <param name="throwExceptions">If true throws exceptions otherwise returns null</param> /// <returns>Dynamic JsonSerializer instance</returns> public static dynamic CreateJsonNet(bool throwExceptions = true) { if (JsonNet != null) return JsonNet; lock (SyncLock) { if (JsonNet != null) return JsonNet; // Try to create instance dynamic json = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.JsonSerializer"); if (json == null) { try { var ass = AppDomain.CurrentDomain.Load("Newtonsoft.Json"); json = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.JsonSerializer"); } catch (Exception ex) { if (throwExceptions) throw; return null; } } if (json == null) return null; json.ReferenceLoopHandling = (dynamic) ReflectionUtils.GetStaticProperty("Newtonsoft.Json.ReferenceLoopHandling", "Ignore"); // Enums as strings in JSON dynamic enumConverter = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.Converters.StringEnumConverter"); json.Converters.Add(enumConverter); JsonNet = json; } return JsonNet; }This code's purpose is to return a fully configured JsonSerializer instance. As you can see the code tries to create an instance and when it fails tries to load the assembly, and then re-tries loading.Once the instance is loaded some configuration occurs on it. Specifically I set the ReferenceLoopHandling option to not blow up immediately when circular references are encountered. There are a host of other small config setting that might be useful to set, but the default seem to be good enough in recent versions. Note that I'm setting ReferenceLoopHandling which requires an Enum value to be set. There's no real easy way (short of using the cardinal numeric value) to set a property or pass parameters from static values or enums. This means I still need to use Reflection to make this work. I'm using the same ReflectionUtils class I previously used to handle this for me. The function looks up the type and then uses Type.InvokeMember() to read the static property.Another feature I need is have Enum values serialized as strings rather than numeric values which is the default. To do this I can use the StringEnumConverter to convert enums to strings by adding it to the Converters collection.As you can see there's still a bit of Reflection to be done even in C# 4+ with dynamic, but with a few helpers this process is relatively painless.Doing the actual JSON ConversionFinally I need to actually do my JSON conversions. For the Utility class I need serialization that works for both strings and files so I created four methods that handle these tasks two each for serialization and deserialization for string and file.Here's what the File Serialization looks like:/// <summary> /// Serializes an object instance to a JSON file. /// </summary> /// <param name="value">the value to serialize</param> /// <param name="fileName">Full path to the file to write out with JSON.</param> /// <param name="throwExceptions">Determines whether exceptions are thrown or false is returned</param> /// <param name="formatJsonOutput">if true pretty-formats the JSON with line breaks</param> /// <returns>true or false</returns> public static bool SerializeToFile(object value, string fileName, bool throwExceptions = false, bool formatJsonOutput = false) { dynamic writer = null; FileStream fs = null; try { Type type = value.GetType(); var json = CreateJsonNet(throwExceptions); if (json == null) return false; fs = new FileStream(fileName, FileMode.Create); var sw = new StreamWriter(fs, Encoding.UTF8); writer = Activator.CreateInstance(JsonTextWriterType, sw); if (formatJsonOutput) writer.Formatting = (dynamic)Enum.Parse(FormattingType, "Indented"); writer.QuoteChar = '"'; json.Serialize(writer, value); } catch (Exception ex) { Debug.WriteLine("JsonSerializer Serialize error: " + ex.Message); if (throwExceptions) throw; return false; } finally { if (writer != null) writer.Close(); if (fs != null) fs.Close(); } return true; }You can see more of the dynamic invocation in this code. First I grab the dynamic JsonSerializer instance using the CreateJsonNet() method shown earlier which returns a dynamic. I then create a JsonTextWriter and configure a couple of enum settings on it, and then call Serialize() on the serializer instance with the JsonTextWriter that writes the output to disk. Although this code is dynamic it's still fairly short and readable.For full circle operation here's the DeserializeFromFile() version:/// <summary> /// Deserializes an object from file and returns a reference. /// </summary> /// <param name="fileName">name of the file to serialize to</param> /// <param name="objectType">The Type of the object. Use typeof(yourobject class)</param> /// <param name="binarySerialization">determines whether we use Xml or Binary serialization</param> /// <param name="throwExceptions">determines whether failure will throw rather than return null on failure</param> /// <returns>Instance of the deserialized object or null. Must be cast to your object type</returns> public static object DeserializeFromFile(string fileName, Type objectType, bool throwExceptions = false) { dynamic json = CreateJsonNet(throwExceptions); if (json == null) return null; object result = null; dynamic reader = null; FileStream fs = null; try { fs = new FileStream(fileName, FileMode.Open, FileAccess.Read); var sr = new StreamReader(fs, Encoding.UTF8); reader = Activator.CreateInstance(JsonTextReaderType, sr); result = json.Deserialize(reader, objectType); reader.Close(); } catch (Exception ex) { Debug.WriteLine("JsonNetSerialization Deserialization Error: " + ex.Message); if (throwExceptions) throw; return null; } finally { if (reader != null) reader.Close(); if (fs != null) fs.Close(); } return result; }This code is a little more compact since there are no prettifying options to set. Here JsonTextReader is created dynamically and it receives the output from the Deserialize() operation on the serializer.You can take a look at the full JsonSerializationUtils.cs file on GitHub to see the rest of the operations, but the string operations are very similar - the code is fairly repetitive.These generic serialization utilities isolate the dynamic serialization logic that has to deal with the dynamic nature of JSON.NET, and any code that uses these functions is none the wiser that JSON.NET is dynamically loaded.Using the JsonSerializationUtils WrapperThe final consumer of the SerializationUtils wrapper is an actual ConfigurationProvider, that is responsible for handling reading and writing JSON values to and from files. The provider is simple a small wrapper around the SerializationUtils component and there's very little code to make this work now:The whole provider looks like this:/// <summary> /// Reads and Writes configuration settings in .NET config files and /// sections. Allows reading and writing to default or external files /// and specification of the configuration section that settings are /// applied to. /// </summary> public class JsonFileConfigurationProvider<TAppConfiguration> : ConfigurationProviderBase<TAppConfiguration> where TAppConfiguration: AppConfiguration, new() { /// <summary> /// Optional - the Configuration file where configuration settings are /// stored in. If not specified uses the default Configuration Manager /// and its default store. /// </summary> public string JsonConfigurationFile { get { return _JsonConfigurationFile; } set { _JsonConfigurationFile = value; } } private string _JsonConfigurationFile = string.Empty; public override bool Read(AppConfiguration config) { var newConfig = JsonSerializationUtils.DeserializeFromFile(JsonConfigurationFile, typeof(TAppConfiguration)) as TAppConfiguration; if (newConfig == null) { if(Write(config)) return true; return false; } DecryptFields(newConfig); DataUtils.CopyObjectData(newConfig, config, "Provider,ErrorMessage"); return true; } /// <summary> /// Return /// </summary> /// <typeparam name="TAppConfig"></typeparam> /// <returns></returns> public override TAppConfig Read<TAppConfig>() { var result = JsonSerializationUtils.DeserializeFromFile(JsonConfigurationFile, typeof(TAppConfig)) as TAppConfig; if (result != null) DecryptFields(result); return result; } /// <summary> /// Write configuration to XmlConfigurationFile location /// </summary> /// <param name="config"></param> /// <returns></returns> public override bool Write(AppConfiguration config) { EncryptFields(config); bool result = JsonSerializationUtils.SerializeToFile(config, JsonConfigurationFile,false,true); // Have to decrypt again to make sure the properties are readable afterwards DecryptFields(config); return result; } }This incidentally demonstrates how easy it is to create a new provider for the West Wind Application Configuration component. Simply implementing 3 methods will do in most cases.Note this code doesn't have any dynamic dependencies - all that's abstracted away in the JsonSerializationUtils(). From here on, serializing JSON is just a matter of calling the static methods on the SerializationUtils class.Already, there are several other places in some other tools where I use JSON serialization this is coming in very handy. With a couple of lines of code I was able to add JSON.NET support to an older AJAX library that I use replacing quite a bit of code that was previously in use. And for any other manual JSON operations (in a couple of apps I use JSON Serialization for 'blob' like document storage) this is also going to be handy.Performance?Some of you might be thinking that using dynamic and Reflection can't be good for performance. And you'd be right… In performing some informal testing it looks like the performance of the native code is nearly twice as fast as the dynamic code. Most of the slowness is attributable to type lookups. To test I created a native class that uses an actual reference to JSON.NET and performance was consistently around 85-90% faster with the referenced code. This will change though depending on the size of objects serialized - the larger the object the more processing time is spent inside the actual dynamically activated components and the less difference there will be. Dynamic code is always slower, but how much it really affects your application primarily depends on how frequently the dynamic code is called in relation to the non-dynamic code executing. In most situations where dynamic code is used 'to get the process rolling' as I do here the overhead is small enough to not matter.All that being said though - I serialized 10,000 objects in 80ms vs. 45ms so this is hardly slouchy performance. For the configuration component speed is not that important because both read and write operations typically happen once on first access and then every once in a while. But for other operations - say a serializer trying to handle AJAX requests on a Web Server one would be well served to create a hard dependency.Dynamic Loading - Worth it?Dynamic loading is not something you need to worry about but on occasion dynamic loading makes sense. But there's a price to be paid in added code  and a performance hit which depends on how frequently the dynamic code is accessed. But for some operations that are not pivotal to a component or application and are only used under certain circumstances dynamic loading can be beneficial to avoid having to ship extra files adding dependencies and loading down distributions. These days when you create new projects in Visual Studio with 30 assemblies before you even add your own code, trying to keep file counts under control seems like a good idea. It's not the kind of thing you do on a regular basis, but when needed it can be a useful option in your toolset… © Rick Strahl, West Wind Technologies, 2005-2013Posted in .NET  C#   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

    Read the article

  • C#/.NET Little Wonders: The Generic Func Delegates

    - by James Michael Hare
    Once again, in this series of posts I look at the parts of the .NET Framework that may seem trivial, but can help improve your code by making it easier to write and maintain. The index of all my past little wonders posts can be found here. Back in one of my three original “Little Wonders” Trilogy of posts, I had listed generic delegates as one of the Little Wonders of .NET.  Later, someone posted a comment saying said that they would love more detail on the generic delegates and their uses, since my original entry just scratched the surface of them. Last week, I began our look at some of the handy generic delegates built into .NET with a description of delegates in general, and the Action family of delegates.  For this week, I’ll launch into a look at the Func family of generic delegates and how they can be used to support generic, reusable algorithms and classes. Quick Delegate Recap Delegates are similar to function pointers in C++ in that they allow you to store a reference to a method.  They can store references to either static or instance methods, and can actually be used to chain several methods together in one delegate. Delegates are very type-safe and can be satisfied with any standard method, anonymous method, or a lambda expression.  They can also be null as well (refers to no method), so care should be taken to make sure that the delegate is not null before you invoke it. Delegates are defined using the keyword delegate, where the delegate’s type name is placed where you would typically place the method name: 1: // This delegate matches any method that takes string, returns nothing 2: public delegate void Log(string message); This delegate defines a delegate type named Log that can be used to store references to any method(s) that satisfies its signature (whether instance, static, lambda expression, etc.). Delegate instances then can be assigned zero (null) or more methods using the operator = which replaces the existing delegate chain, or by using the operator += which adds a method to the end of a delegate chain: 1: // creates a delegate instance named currentLogger defaulted to Console.WriteLine (static method) 2: Log currentLogger = Console.Out.WriteLine; 3:  4: // invokes the delegate, which writes to the console out 5: currentLogger("Hi Standard Out!"); 6:  7: // append a delegate to Console.Error.WriteLine to go to std error 8: currentLogger += Console.Error.WriteLine; 9:  10: // invokes the delegate chain and writes message to std out and std err 11: currentLogger("Hi Standard Out and Error!"); While delegates give us a lot of power, it can be cumbersome to re-create fairly standard delegate definitions repeatedly, for this purpose the generic delegates were introduced in various stages in .NET.  These support various method types with particular signatures. Note: a caveat with generic delegates is that while they can support multiple parameters, they do not match methods that contains ref or out parameters. If you want to a delegate to represent methods that takes ref or out parameters, you will need to create a custom delegate. We’ve got the Func… delegates Just like it’s cousin, the Action delegate family, the Func delegate family gives us a lot of power to use generic delegates to make classes and algorithms more generic.  Using them keeps us from having to define a new delegate type when need to make a class or algorithm generic. Remember that the point of the Action delegate family was to be able to perform an “action” on an item, with no return results.  Thus Action delegates can be used to represent most methods that take 0 to 16 arguments but return void.  You can assign a method The Func delegate family was introduced in .NET 3.5 with the advent of LINQ, and gives us the power to define a function that can be called on 0 to 16 arguments and returns a result.  Thus, the main difference between Action and Func, from a delegate perspective, is that Actions return nothing, but Funcs return a result. The Func family of delegates have signatures as follows: Func<TResult> – matches a method that takes no arguments, and returns value of type TResult. Func<T, TResult> – matches a method that takes an argument of type T, and returns value of type TResult. Func<T1, T2, TResult> – matches a method that takes arguments of type T1 and T2, and returns value of type TResult. Func<T1, T2, …, TResult> – and so on up to 16 arguments, and returns value of type TResult. These are handy because they quickly allow you to be able to specify that a method or class you design will perform a function to produce a result as long as the method you specify meets the signature. For example, let’s say you were designing a generic aggregator, and you wanted to allow the user to define how the values will be aggregated into the result (i.e. Sum, Min, Max, etc…).  To do this, we would ask the user of our class to pass in a method that would take the current total, the next value, and produce a new total.  A class like this could look like: 1: public sealed class Aggregator<TValue, TResult> 2: { 3: // holds method that takes previous result, combines with next value, creates new result 4: private Func<TResult, TValue, TResult> _aggregationMethod; 5:  6: // gets or sets the current result of aggregation 7: public TResult Result { get; private set; } 8:  9: // construct the aggregator given the method to use to aggregate values 10: public Aggregator(Func<TResult, TValue, TResult> aggregationMethod = null) 11: { 12: if (aggregationMethod == null) throw new ArgumentNullException("aggregationMethod"); 13:  14: _aggregationMethod = aggregationMethod; 15: } 16:  17: // method to add next value 18: public void Aggregate(TValue nextValue) 19: { 20: // performs the aggregation method function on the current result and next and sets to current result 21: Result = _aggregationMethod(Result, nextValue); 22: } 23: } Of course, LINQ already has an Aggregate extension method, but that works on a sequence of IEnumerable<T>, whereas this is designed to work more with aggregating single results over time (such as keeping track of a max response time for a service). We could then use this generic aggregator to find the sum of a series of values over time, or the max of a series of values over time (among other things): 1: // creates an aggregator that adds the next to the total to sum the values 2: var sumAggregator = new Aggregator<int, int>((total, next) => total + next); 3:  4: // creates an aggregator (using static method) that returns the max of previous result and next 5: var maxAggregator = new Aggregator<int, int>(Math.Max); So, if we were timing the response time of a web method every time it was called, we could pass that response time to both of these aggregators to get an idea of the total time spent in that web method, and the max time spent in any one call to the web method: 1: // total will be 13 and max 13 2: int responseTime = 13; 3: sumAggregator.Aggregate(responseTime); 4: maxAggregator.Aggregate(responseTime); 5:  6: // total will be 20 and max still 13 7: responseTime = 7; 8: sumAggregator.Aggregate(responseTime); 9: maxAggregator.Aggregate(responseTime); 10:  11: // total will be 40 and max now 20 12: responseTime = 20; 13: sumAggregator.Aggregate(responseTime); 14: maxAggregator.Aggregate(responseTime); The Func delegate family is useful for making generic algorithms and classes, and in particular allows the caller of the method or user of the class to specify a function to be performed in order to generate a result. What is the result of a Func delegate chain? If you remember, we said earlier that you can assign multiple methods to a delegate by using the += operator to chain them.  So how does this affect delegates such as Func that return a value, when applied to something like the code below? 1: Func<int, int, int> combo = null; 2:  3: // What if we wanted to aggregate the sum and max together? 4: combo += (total, next) => total + next; 5: combo += Math.Max; 6:  7: // what is the result? 8: var comboAggregator = new Aggregator<int, int>(combo); Well, in .NET if you chain multiple methods in a delegate, they will all get invoked, but the result of the delegate is the result of the last method invoked in the chain.  Thus, this aggregator would always result in the Math.Max() result.  The other chained method (the sum) gets executed first, but it’s result is thrown away: 1: // result is 13 2: int responseTime = 13; 3: comboAggregator.Aggregate(responseTime); 4:  5: // result is still 13 6: responseTime = 7; 7: comboAggregator.Aggregate(responseTime); 8:  9: // result is now 20 10: responseTime = 20; 11: comboAggregator.Aggregate(responseTime); So remember, you can chain multiple Func (or other delegates that return values) together, but if you do so you will only get the last executed result. Func delegates and co-variance/contra-variance in .NET 4.0 Just like the Action delegate, as of .NET 4.0, the Func delegate family is contra-variant on its arguments.  In addition, it is co-variant on its return type.  To support this, in .NET 4.0 the signatures of the Func delegates changed to: Func<out TResult> – matches a method that takes no arguments, and returns value of type TResult (or a more derived type). Func<in T, out TResult> – matches a method that takes an argument of type T (or a less derived type), and returns value of type TResult(or a more derived type). Func<in T1, in T2, out TResult> – matches a method that takes arguments of type T1 and T2 (or less derived types), and returns value of type TResult (or a more derived type). Func<in T1, in T2, …, out TResult> – and so on up to 16 arguments, and returns value of type TResult (or a more derived type). Notice the addition of the in and out keywords before each of the generic type placeholders.  As we saw last week, the in keyword is used to specify that a generic type can be contra-variant -- it can match the given type or a type that is less derived.  However, the out keyword, is used to specify that a generic type can be co-variant -- it can match the given type or a type that is more derived. On contra-variance, if you are saying you need an function that will accept a string, you can just as easily give it an function that accepts an object.  In other words, if you say “give me an function that will process dogs”, I could pass you a method that will process any animal, because all dogs are animals.  On the co-variance side, if you are saying you need a function that returns an object, you can just as easily pass it a function that returns a string because any string returned from the given method can be accepted by a delegate expecting an object result, since string is more derived.  Once again, in other words, if you say “give me a method that creates an animal”, I can pass you a method that will create a dog, because all dogs are animals. It really all makes sense, you can pass a more specific thing to a less specific parameter, and you can return a more specific thing as a less specific result.  In other words, pay attention to the direction the item travels (parameters go in, results come out).  Keeping that in mind, you can always pass more specific things in and return more specific things out. For example, in the code below, we have a method that takes a Func<object> to generate an object, but we can pass it a Func<string> because the return type of object can obviously accept a return value of string as well: 1: // since Func<object> is co-variant, this will access Func<string>, etc... 2: public static string Sequence(int count, Func<object> generator) 3: { 4: var builder = new StringBuilder(); 5:  6: for (int i=0; i<count; i++) 7: { 8: object value = generator(); 9: builder.Append(value); 10: } 11:  12: return builder.ToString(); 13: } Even though the method above takes a Func<object>, we can pass a Func<string> because the TResult type placeholder is co-variant and accepts types that are more derived as well: 1: // delegate that's typed to return string. 2: Func<string> stringGenerator = () => DateTime.Now.ToString(); 3:  4: // This will work in .NET 4.0, but not in previous versions 5: Sequence(100, stringGenerator); Previous versions of .NET implemented some forms of co-variance and contra-variance before, but .NET 4.0 goes one step further and allows you to pass or assign an Func<A, BResult> to a Func<Y, ZResult> as long as A is less derived (or same) as Y, and BResult is more derived (or same) as ZResult. Sidebar: The Func and the Predicate A method that takes one argument and returns a bool is generally thought of as a predicate.  Predicates are used to examine an item and determine whether that item satisfies a particular condition.  Predicates are typically unary, but you may also have binary and other predicates as well. Predicates are often used to filter results, such as in the LINQ Where() extension method: 1: var numbers = new[] { 1, 2, 4, 13, 8, 10, 27 }; 2:  3: // call Where() using a predicate which determines if the number is even 4: var evens = numbers.Where(num => num % 2 == 0); As of .NET 3.5, predicates are typically represented as Func<T, bool> where T is the type of the item to examine.  Previous to .NET 3.5, there was a Predicate<T> type that tended to be used (which we’ll discuss next week) and is still supported, but most developers recommend using Func<T, bool> now, as it prevents confusion with overloads that accept unary predicates and binary predicates, etc.: 1: // this seems more confusing as an overload set, because of Predicate vs Func 2: public static SomeMethod(Predicate<int> unaryPredicate) { } 3: public static SomeMethod(Func<int, int, bool> binaryPredicate) { } 4:  5: // this seems more consistent as an overload set, since just uses Func 6: public static SomeMethod(Func<int, bool> unaryPredicate) { } 7: public static SomeMethod(Func<int, int, bool> binaryPredicate) { } Also, even though Predicate<T> and Func<T, bool> match the same signatures, they are separate types!  Thus you cannot assign a Predicate<T> instance to a Func<T, bool> instance and vice versa: 1: // the same method, lambda expression, etc can be assigned to both 2: Predicate<int> isEven = i => (i % 2) == 0; 3: Func<int, bool> alsoIsEven = i => (i % 2) == 0; 4:  5: // but the delegate instances cannot be directly assigned, strongly typed! 6: // ERROR: cannot convert type... 7: isEven = alsoIsEven; 8:  9: // however, you can assign by wrapping in a new instance: 10: isEven = new Predicate<int>(alsoIsEven); 11: alsoIsEven = new Func<int, bool>(isEven); So, the general advice that seems to come from most developers is that Predicate<T> is still supported, but we should use Func<T, bool> for consistency in .NET 3.5 and above. Sidebar: Func as a Generator for Unit Testing One area of difficulty in unit testing can be unit testing code that is based on time of day.  We’d still want to unit test our code to make sure the logic is accurate, but we don’t want the results of our unit tests to be dependent on the time they are run. One way (of many) around this is to create an internal generator that will produce the “current” time of day.  This would default to returning result from DateTime.Now (or some other method), but we could inject specific times for our unit testing.  Generators are typically methods that return (generate) a value for use in a class/method. For example, say we are creating a CacheItem<T> class that represents an item in the cache, and we want to make sure the item shows as expired if the age is more than 30 seconds.  Such a class could look like: 1: // responsible for maintaining an item of type T in the cache 2: public sealed class CacheItem<T> 3: { 4: // helper method that returns the current time 5: private static Func<DateTime> _timeGenerator = () => DateTime.Now; 6:  7: // allows internal access to the time generator 8: internal static Func<DateTime> TimeGenerator 9: { 10: get { return _timeGenerator; } 11: set { _timeGenerator = value; } 12: } 13:  14: // time the item was cached 15: public DateTime CachedTime { get; private set; } 16:  17: // the item cached 18: public T Value { get; private set; } 19:  20: // item is expired if older than 30 seconds 21: public bool IsExpired 22: { 23: get { return _timeGenerator() - CachedTime > TimeSpan.FromSeconds(30.0); } 24: } 25:  26: // creates the new cached item, setting cached time to "current" time 27: public CacheItem(T value) 28: { 29: Value = value; 30: CachedTime = _timeGenerator(); 31: } 32: } Then, we can use this construct to unit test our CacheItem<T> without any time dependencies: 1: var baseTime = DateTime.Now; 2:  3: // start with current time stored above (so doesn't drift) 4: CacheItem<int>.TimeGenerator = () => baseTime; 5:  6: var target = new CacheItem<int>(13); 7:  8: // now add 15 seconds, should still be non-expired 9: CacheItem<int>.TimeGenerator = () => baseTime.AddSeconds(15); 10:  11: Assert.IsFalse(target.IsExpired); 12:  13: // now add 31 seconds, should now be expired 14: CacheItem<int>.TimeGenerator = () => baseTime.AddSeconds(31); 15:  16: Assert.IsTrue(target.IsExpired); Now we can unit test for 1 second before, 1 second after, 1 millisecond before, 1 day after, etc.  Func delegates can be a handy tool for this type of value generation to support more testable code.  Summary Generic delegates give us a lot of power to make truly generic algorithms and classes.  The Func family of delegates is a great way to be able to specify functions to calculate a result based on 0-16 arguments.  Stay tuned in the weeks that follow for other generic delegates in the .NET Framework!   Tweet Technorati Tags: .NET, C#, CSharp, Little Wonders, Generics, Func, Delegates

    Read the article

  • How to create Custom ListForm WebPart

    - by DipeshBhanani
    Mostly all who works extensively on SharePoint (including meJ) don’t like to use out-of-box list forms (DispForm.aspx, EditForm.aspx, NewForm.aspx) as interface. Actually these OOB list forms bind hands of developers for the customization. It gives headache to developers to add just one post back event, for a dropdown field and to populate other fields in NewForm.aspx or EditForm.aspx. On top of that clients always ask such stuff. So here I am going to give you guys a flight for SharePoint Customization world. In this blog, I will explain, how to create CustomListForm WebPart. In my next blogs, I am going to explain easy deployment of List Forms through features and last, guidance on using SharePoint web controls. 1.       First thing, create a class library project through Visual Studio and inherit the class with WebPart class.     public class CustomListForm : WebPart   2.       Declare the public variables and properties which we are going to use throughout the class. You will get to know these once you see them in use.         #region "Variable Declaration"           Table spTableCntl;         FormToolBar formToolBar;         Literal ltAlertMessage;         Guid SiteId;         Guid ListId;         int ItemId;         string ListName;           #endregion           #region "Properties"           SPControlMode _ControlMode = SPControlMode.New;         [Personalizable(PersonalizationScope.Shared),          WebBrowsable(true),          WebDisplayName("Control Mode"),          WebDescription("Set Control Mode"),          DefaultValue(""),          Category("Miscellaneous")]         public SPControlMode ControlMode         {             get { return _ControlMode; }             set { _ControlMode = value; }         }           #endregion     The property “ControlMode” is used to identify the mode of the List Form. The property is of type SPControlMode which is an enum type with values (Display, Edit, New and Invalid). When we will add this WebPart to DispForm.aspx, EditForm.aspx and NewForm.aspx, we will set the WebPart property “ControlMode” to Display, Edit and New respectively.     3.       Now, we need to override the CreateChildControl method and write code to manually add SharePoint Web Controls related to each list fields as well as ToolBar controls.         protected override void CreateChildControls()         {             base.CreateChildControls();               try             {                 SiteId = SPContext.Current.Site.ID;                 ListId = SPContext.Current.ListId;                 ListName = SPContext.Current.List.Title;                   if (_ControlMode == SPControlMode.Display || _ControlMode == SPControlMode.Edit)                     ItemId = SPContext.Current.ItemId;                   SPSecurity.RunWithElevatedPrivileges(delegate()                 {                     using (SPSite site = new SPSite(SiteId))                     {                         //creating a new SPSite with credentials of System Account                         using (SPWeb web = site.OpenWeb())                         {                               //<Custom Code for creating form controls>                         }                     }                 });             }             catch (Exception ex)             {                 ShowError(ex, "CreateChildControls");             }         }   Here we are assuming that we are developing this WebPart to plug into List Forms. Hence we will get the List Id and List Name from the current context. We can have Item Id only in case of Display and Edit Mode. We are putting our code into “RunWithElevatedPrivileges” to elevate privileges to System Account. Now, let’s get deep down into the main code and expand “//<Custom Code for creating form controls>”. Before initiating any SharePoint control, we need to set context of SharePoint web controls explicitly so that it will be instantiated with elevated System Account user. Following line does the job.     //To create SharePoint controls with new web object and System Account credentials     SPControl.SetContextWeb(Context, web);   First thing, let’s add main table as container for all controls.     //Table to render webpart     Table spTableMain = new Table();     spTableMain.CellPadding = 0;     spTableMain.CellSpacing = 0;     spTableMain.Width = new Unit(100, UnitType.Percentage);     this.Controls.Add(spTableMain);   Now we need to add Top toolbar with Save and Cancel button at top as you see in the below screen shot.       // Add Row and Cell for Top ToolBar     TableRow spRowTopToolBar = new TableRow();     spTableMain.Rows.Add(spRowTopToolBar);     TableCell spCellTopToolBar = new TableCell();     spRowTopToolBar.Cells.Add(spCellTopToolBar);     spCellTopToolBar.Width = new Unit(100, UnitType.Percentage);         ToolBar toolBarTop = (ToolBar)Page.LoadControl("/_controltemplates/ToolBar.ascx");     toolBarTop.CssClass = "ms-formtoolbar";     toolBarTop.ID = "toolBarTbltop";     toolBarTop.RightButtons.SeparatorHtml = "<td class=ms-separator> </td>";       if (_ControlMode != SPControlMode.Display)     {         SaveButton btnSave = new SaveButton();         btnSave.ControlMode = _ControlMode;         btnSave.ListId = ListId;           if (_ControlMode == SPControlMode.New)             btnSave.RenderContext = SPContext.GetContext(web);         else         {             btnSave.RenderContext = SPContext.GetContext(this.Context, ItemId, ListId, web);             btnSave.ItemContext = SPContext.GetContext(this.Context, ItemId, ListId, web);             btnSave.ItemId = ItemId;         }         toolBarTop.RightButtons.Controls.Add(btnSave);     }       GoBackButton goBackButtonTop = new GoBackButton();     toolBarTop.RightButtons.Controls.Add(goBackButtonTop);     goBackButtonTop.ControlMode = SPControlMode.Display;       spCellTopToolBar.Controls.Add(toolBarTop);   Here we have use “SaveButton” and “GoBackButton” which are internal SharePoint web controls for save and cancel functionality. I have set some of the properties of Save Button with if-else condition because we will not have Item Id in case of New Mode. Item Id property is used to identify which SharePoint List Item need to be saved. Now, add Form Toolbar to the page which contains “Attach File”, “Delete Item” etc buttons.       // Add Row and Cell for FormToolBar     TableRow spRowFormToolBar = new TableRow();     spTableMain.Rows.Add(spRowFormToolBar);     TableCell spCellFormToolBar = new TableCell();     spRowFormToolBar.Cells.Add(spCellFormToolBar);     spCellFormToolBar.Width = new Unit(100, UnitType.Percentage);       FormToolBar formToolBar = new FormToolBar();     formToolBar.ID = "formToolBar";     formToolBar.ListId = ListId;     if (_ControlMode == SPControlMode.New)         formToolBar.RenderContext = SPContext.GetContext(web);     else     {         formToolBar.RenderContext = SPContext.GetContext(this.Context, ItemId, ListId, web);         formToolBar.ItemContext = SPContext.GetContext(this.Context, ItemId, ListId, web);         formToolBar.ItemId = ItemId;     }     formToolBar.ControlMode = _ControlMode;     formToolBar.EnableViewState = true;       spCellFormToolBar.Controls.Add(formToolBar);     The ControlMode property will take care of which button to be displayed on the toolbar. E.g. “Attach files”, “Delete Item” in new/edit forms and “New Item”, “Edit Item”, “Delete Item”, “Manage Permissions” etc in display forms. Now add main section which contains form field controls.     //Create Form Field controls and add them in Table "spCellCntl"     CreateFieldControls(web);     //Add public variable "spCellCntl" containing all form controls to the page     spRowCntl.Cells.Add(spCellCntl);     spCellCntl.Width = new Unit(100, UnitType.Percentage);     spCellCntl.Controls.Add(spTableCntl);       //Add a Blank Row with height of 5px to render space between ToolBar table and Control table     TableRow spRowLine1 = new TableRow();     spTableMain.Rows.Add(spRowLine1);     TableCell spCellLine1 = new TableCell();     spRowLine1.Cells.Add(spCellLine1);     spCellLine1.Height = new Unit(5, UnitType.Pixel);     spCellLine1.Controls.Add(new LiteralControl("<IMG SRC='/_layouts/images/blank.gif' width=1 height=1 alt=''>"));       //Add Row and Cell for Form Controls Section     TableRow spRowCntl = new TableRow();     spTableMain.Rows.Add(spRowCntl);     TableCell spCellCntl = new TableCell();       //Create Form Field controls and add them in Table "spCellCntl"     CreateFieldControls(web);     //Add public variable "spCellCntl" containing all form controls to the page     spRowCntl.Cells.Add(spCellCntl);     spCellCntl.Width = new Unit(100, UnitType.Percentage);     spCellCntl.Controls.Add(spTableCntl);       TableRow spRowLine2 = new TableRow();     spTableMain.Rows.Add(spRowLine2);     TableCell spCellLine2 = new TableCell();     spRowLine2.Cells.Add(spCellLine2);     spCellLine2.CssClass = "ms-formline";     spCellLine2.Controls.Add(new LiteralControl("<IMG SRC='/_layouts/images/blank.gif' width=1 height=1 alt=''>"));       // Add Blank row with height of 5 pixel     TableRow spRowLine3 = new TableRow();     spTableMain.Rows.Add(spRowLine3);     TableCell spCellLine3 = new TableCell();     spRowLine3.Cells.Add(spCellLine3);     spCellLine3.Height = new Unit(5, UnitType.Pixel);     spCellLine3.Controls.Add(new LiteralControl("<IMG SRC='/_layouts/images/blank.gif' width=1 height=1 alt=''>"));   You can add bottom toolbar also to get same look and feel as OOB forms. I am not adding here as the blog will be much lengthy. At last, you need to write following lines to allow unsafe updates for Save and Delete button.     // Allow unsafe update on web for save button and delete button     if (this.Page.IsPostBack && this.Page.Request["__EventTarget"] != null         && (this.Page.Request["__EventTarget"].Contains("IOSaveItem")         || this.Page.Request["__EventTarget"].Contains("IODeleteItem")))     {         SPContext.Current.Web.AllowUnsafeUpdates = true;     }   So that’s all. We have finished writing Custom Code for adding field control. But something most important is skipped. In above code, I have called function “CreateFieldControls(web);” to add SharePoint field controls to the page. Let’s see the implementation of the function:     private void CreateFieldControls(SPWeb pWeb)     {         SPList listMain = pWeb.Lists[ListId];         SPFieldCollection fields = listMain.Fields;           //Main Table to render all fields         spTableCntl = new Table();         spTableCntl.BorderWidth = new Unit(0);         spTableCntl.CellPadding = 0;         spTableCntl.CellSpacing = 0;         spTableCntl.Width = new Unit(100, UnitType.Percentage);         spTableCntl.CssClass = "ms-formtable";           SPContext controlContext = SPContext.GetContext(this.Context, ItemId, ListId, pWeb);           foreach (SPField listField in fields)         {             string fieldDisplayName = listField.Title;             string fieldInternalName = listField.InternalName;               //Skip if the field is system field or hidden             if (listField.Hidden || listField.ShowInVersionHistory == false)                 continue;               //Skip if the control mode is display and field is read-only             if (_ControlMode != SPControlMode.Display && listField.ReadOnlyField == true)                 continue;               FieldLabel fieldLabel = new FieldLabel();             fieldLabel.FieldName = listField.InternalName;             fieldLabel.ListId = ListId;               BaseFieldControl fieldControl = listField.FieldRenderingControl;             fieldControl.ListId = ListId;             //Assign unique id using Field Internal Name             fieldControl.ID = string.Format("Field_{0}", fieldInternalName);             fieldControl.EnableViewState = true;               //Assign control mode             fieldLabel.ControlMode = _ControlMode;             fieldControl.ControlMode = _ControlMode;             switch (_ControlMode)             {                 case SPControlMode.New:                     fieldLabel.RenderContext = SPContext.GetContext(pWeb);                     fieldControl.RenderContext = SPContext.GetContext(pWeb);                     break;                 case SPControlMode.Edit:                 case SPControlMode.Display:                     fieldLabel.RenderContext = controlContext;                     fieldLabel.ItemContext = controlContext;                     fieldLabel.ItemId = ItemId;                       fieldControl.RenderContext = controlContext;                     fieldControl.ItemContext = controlContext;                     fieldControl.ItemId = ItemId;                     break;             }               //Add row to display a field row             TableRow spCntlRow = new TableRow();             spTableCntl.Rows.Add(spCntlRow);               //Add the cells for containing field lable and control             TableCell spCellLabel = new TableCell();             spCellLabel.Width = new Unit(30, UnitType.Percentage);             spCellLabel.CssClass = "ms-formlabel";             spCntlRow.Cells.Add(spCellLabel);             TableCell spCellControl = new TableCell();             spCellControl.Width = new Unit(70, UnitType.Percentage);             spCellControl.CssClass = "ms-formbody";             spCntlRow.Cells.Add(spCellControl);               //Add the control to the table cells             spCellLabel.Controls.Add(fieldLabel);             spCellControl.Controls.Add(fieldControl);               //Add description if there is any in case of New and Edit Mode             if (_ControlMode != SPControlMode.Display && listField.Description != string.Empty)             {                 FieldDescription fieldDesc = new FieldDescription();                 fieldDesc.FieldName = fieldInternalName;                 fieldDesc.ListId = ListId;                 spCellControl.Controls.Add(fieldDesc);             }               //Disable Name(Title) in Edit Mode             if (_ControlMode == SPControlMode.Edit && fieldDisplayName == "Name")             {                 TextBox txtTitlefield = (TextBox)fieldControl.Controls[0].FindControl("TextField");                 txtTitlefield.Enabled = false;             }         }         fields = null;     }   First of all, I have declared List object and got list fields in field collection object called “fields”. Then I have added a table for the container of all controls and assign CSS class as "ms-formtable" so that it gives consistent look and feel of SharePoint. Now it’s time to navigate through all fields and add them if required. Here we don’t need to add hidden or system fields. We also don’t want to display read-only fields in new and edit forms. Following lines does this job.             //Skip if the field is system field or hidden             if (listField.Hidden || listField.ShowInVersionHistory == false)                 continue;               //Skip if the control mode is display and field is read-only             if (_ControlMode != SPControlMode.Display && listField.ReadOnlyField == true)                 continue;   Let’s move to the next line of code.             FieldLabel fieldLabel = new FieldLabel();             fieldLabel.FieldName = listField.InternalName;             fieldLabel.ListId = ListId;               BaseFieldControl fieldControl = listField.FieldRenderingControl;             fieldControl.ListId = ListId;             //Assign unique id using Field Internal Name             fieldControl.ID = string.Format("Field_{0}", fieldInternalName);             fieldControl.EnableViewState = true;               //Assign control mode             fieldLabel.ControlMode = _ControlMode;             fieldControl.ControlMode = _ControlMode;   We have used “FieldLabel” control for displaying field title. The advantage of using Field Label is, SharePoint automatically adds red star besides field label to identify it as mandatory field if there is any. Here is most important part to understand. The “BaseFieldControl”. It will render the respective web controls according to type of the field. For example, if it’s single line of text, then Textbox, if it’s look up then it renders dropdown. Additionally, the “ControlMode” property tells compiler that which mode (display/edit/new) controls need to be rendered with. In display mode, it will render label with field value. In edit mode, it will render respective control with item value and in new mode it will render respective control with empty value. Please note that, it’s not always the case when dropdown field will be rendered for Lookup field or Choice field. You need to understand which controls are rendered for which list fields. I am planning to write a separate blog which I hope to publish it very soon. Moreover, we also need to assign list field specific properties like List Id, Field Name etc to identify which SharePoint List field is attached with the control.             switch (_ControlMode)             {                 case SPControlMode.New:                     fieldLabel.RenderContext = SPContext.GetContext(pWeb);                     fieldControl.RenderContext = SPContext.GetContext(pWeb);                     break;                 case SPControlMode.Edit:                 case SPControlMode.Display:                     fieldLabel.RenderContext = controlContext;                     fieldLabel.ItemContext = controlContext;                     fieldLabel.ItemId = ItemId;                       fieldControl.RenderContext = controlContext;                     fieldControl.ItemContext = controlContext;                     fieldControl.ItemId = ItemId;                     break;             }   Here, I have separate code for new mode and Edit/Display mode because we will not have Item Id to assign in New Mode. We also need to set CSS class for cell containing Label and Controls so that those controls get rendered with SharePoint theme.             spCellLabel.CssClass = "ms-formlabel";             spCellControl.CssClass = "ms-formbody";   “FieldDescription” control is used to add field description if there is any.    Now it’s time to add some more customization,               //Disable Name(Title) in Edit Mode             if (_ControlMode == SPControlMode.Edit && fieldDisplayName == "Name")             {                 TextBox txtTitlefield = (TextBox)fieldControl.Controls[0].FindControl("TextField");                 txtTitlefield.Enabled = false;             }   The above code will disable the title field in edit mode. You can add more code here to achieve more customization according to your requirement. Some of the examples are as follow:             //Adding post back event on UserField to auto populate some other dependent field             //in new mode and disable it in edit mode             if (_ControlMode != SPControlMode.Display && fieldDisplayName == "Manager")             {                 if (fieldControl.Controls[0].FindControl("UserField") != null)                 {                     PeopleEditor pplEditor = (PeopleEditor)fieldControl.Controls[0].FindControl("UserField");                     if (_ControlMode == SPControlMode.New)                         pplEditor.AutoPostBack = true;                     else                         pplEditor.Enabled = false;                 }             }               //Add JavaScript Event on Dropdown field. Don't forget to add the JavaScript function on the page.             if (_ControlMode == SPControlMode.Edit && fieldDisplayName == "Designation")             {                 DropDownList ddlCategory = (DropDownList)fieldControl.Controls[0];                 ddlCategory.Attributes.Add("onchange", string.Format("javascript:DropdownChangeEvent('{0}');return false;", ddlCategory.ClientID));             }    Following are the screenshots of my Custom ListForm WebPart. Let’s play a game, check out your OOB List forms of SharePoint, compare with these screens and find out differences.   DispForm.aspx:   EditForm.aspx:   NewForm.aspx:   Enjoy the SharePoint Soup!!! ­­­­­­­­­­­­­­­­­­­­

    Read the article

  • ie7 innerhtml strange display problem

    - by thoraniann
    Hello, I am having a strange problem with ie7 (ie8 in compatibility mode). I have div containers where I am updating values using javascript innhtml to update the values. This works fine in Firefox and ie8. In ie7 the values do not update but if a click on the values and highlight them then they update, also if a change the height of the browser then on the next update the values get updated correctly. I have figured out that if I change the position property of the outer div container from relative to static then the updates work correctly. The page can be viewed here http://islendingasogur.net/test/webmap_html_test.html In internet explorer 8 with compatibility turned on you can see that the timestamp in the gray box only gets updated one time, after that you see no changes. The timestamp in the lower right corner gets updated every 10 seconds. But if you highlight the text in the gray box then the updated timestamp values appears! Here is the page: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" /> <meta http-equiv="cache-control" content="no-cache"/> <meta http-equiv="pragma" content="no-cache"/> <meta http-equiv="expires" content="Mon, 22 Jul 2002 11:12:01 GMT"/> <title>innerhtml problem</title> <script type="text/javascript"> <!-- var alarm_off_color = '#00ff00'; var alarm_low_color = '#ffff00'; var alarm_lowlow_color = '#ff0000'; var group_id_array = new Array(); var var_alarm_array = new Array(); var timestamp_color = '#F3F3F3'; var timestamp_alarm_color = '#ff00ff'; group_id_array[257] = 0; function updateParent(var_array, group_array) { //Update last update time var time_str = "Last Reload Time: "; var currentTime = new Date(); var hours = currentTime.getHours(); var minutes = currentTime.getMinutes(); var seconds = currentTime.getSeconds(); if(minutes < 10) {minutes = "0" + minutes;} if(seconds < 10) {seconds = "0" + seconds;} time_str += hours + ":" + minutes + ":" + seconds; document.getElementById('div_last_update_time').innerHTML = time_str; //alert(time_str); alarm_var = 0; //update group values for(i1 = 0; i1 < var_array.length; ++i1) { if(document.getElementById(var_array[i1][0])) { document.getElementById(var_array[i1][0]).innerHTML = unescape(var_array[i1][1]); if(var_array[i1][2]==0) {document.getElementById(var_array[i1][0]).style.backgroundColor=alarm_off_color} else if(var_array[i1][2]==1) {document.getElementById(var_array[i1][0]).style.backgroundColor=alarm_low_color} else if(var_array[i1][2]==2) {document.getElementById(var_array[i1][0]).style.backgroundColor=alarm_lowlow_color} //check if alarm is new var_id = var_array[i1][3]; if(var_array[i1][2]==1 && var_array[i1][4]==0) { alarm_var = 1; } else if(var_array[i1][2]==2 && var_array[i1][4]==0) { alarm_var = 1; } } } //Update group timestamp and box alarm color for(i1 = 0; i1 < group_array.length; ++i1) { if(document.getElementById(group_array[i1][0])) { //set timestamp for group document.getElementById(group_array[i1][0]).innerHTML = group_array[i1][1]; if(group_array[i1][4] != -1) { //set data update error status current_timestamp_color = timestamp_color; if(group_array[i1][4] == 1) {current_timestamp_color = timestamp_alarm_color;} document.getElementById(group_array[i1][0]).style.backgroundColor = current_timestamp_color; } } } } function update_map(map_id) { document.getElementById('webmap_update').src = 'webmap_html_test_sub.html?first_time=1&map_id='+map_id; } --> </script> <style type="text/css"> body { margin:0; border:0; padding:0px;background:#eaeaea;font-family:verdana, arial, sans-serif; text-align: center; } A:active { color: #000000;} A:link { color: #000000;} A:visited { color: #000000;} A:hover { color: #000000;} #div_header { /*position: absolute;*/ background: #ffffff; width: 884px; height: 60px; display: block; float: left; font-size: 14px; text-align: left; /*overflow: visible;*/ } #div_container{ background: #ffffff;border-left:1px solid #000000; border-right:1px solid #000000; border-bottom:1px solid #000000; float: left; width: 884px;} #div_image_container{ position: relative; width: 884px; height: 549px; background: #ffffff; font-family:arial, verdana, arial, sans-serif; /*display: block;*/ float:none!important; float/**/:left; border:1px solid #00ff00; padding: 0px; } .div_group_box{ position: absolute; width: -2px; height: -2px; background: #FFFFFF; opacity: 1; filter: alpha(opacity=100); border:1px solid #000000; font-size: 2px; z-index: 0; padding: 0px; } .div_group_container{ position: absolute; opacity: 1; filter: alpha(opacity=100); z-index: 5; /*display: block;*/ /*border:1px solid #000000;*/ } .div_group_container A:active {text-decoration: none; display: block;} .div_group_container A:link { color: #000000;text-decoration: none; display: block;} .div_group_container A:visited { color: #000000;text-decoration: none; display: block;} .div_group_container A:hover { color: #000000;text-decoration: none; display: block;} .div_group_header{ background: #17B400; border:1px solid #000000;font-size: 12px; color: #FFFFFF; padding-top: 1px; padding-bottom: 1px; padding-left: 2px; padding-right: 2px; text-align: center; } .div_var_name_container{ color: #000000;background: #FFFFFF; border-left:1px solid #000000; border-top:0px solid #000000; border-bottom:0px solid #000000;font-size: 12px; float: left; display: block; text-align: left; } .div_var_name{ padding-top: 1px; padding-bottom: 1px; padding-left: 2px; padding-right: 2px; display: block; } .div_var_value_container{ color: #000000;background: #FFFFFF; border-left:1px solid #000000; border-right:1px solid #000000; border-top:0px solid #000000; border-bottom:0px solid #000000;font-size: 12px; float: left; text-align: center; } .div_var_value{ padding-top: 1px; padding-bottom: 1px; padding-left: 2px; padding-right: 2px; } .div_var_unit_container{ color: #000000;background: #FFFFFF; border-right:1px solid #000000; border-top:0px solid #000000; border-bottom:0px solid #000000;font-size: 12px; float: left; text-align: left; } .div_var_unit{ padding-top: 1px; padding-bottom: 1px; padding-left: 2px; padding-right: 2px; } .div_timestamp{ float: none; color: #000000;background: #F3F3F3; border:1px solid #000000;font-size: 12px; padding-top: 1px; padding-bottom: 1px; padding-left: 2px; padding-right: 2px; text-align: center; clear: left; z-index: 100; position: relative; } #div_last_update_time{ height: 14px; width: 210px; text-align: right; padding: 1px; font-size: 10px; float: right; } .copyright{ height: 14px; width: 240px; text-align: left; color: #777; padding: 1px; font-size: 10px; float: left; } a img { border: 1px solid #000000; } .clearer { clear: both; display: block; height: 1px; margin-bottom: -1px; font-size: 1px; line-height: 1px; } </style> </head> <body onload="update_map(1)"> <div id="div_container"><div id="div_header"></div><div class="clearer"></div><div id="div_image_container"><img id="map" src="Images/maps/0054_gardabaer.jpg" title="My map" alt="" align="left" border="0" usemap ="#_area_links" style="padding: 0px; margin: 0px;" /> <div id="group_container_257" class="div_group_container" style="visibility:visible; top:10px; left:260px; cursor: pointer;"> <div class="div_group_header" style="clear:right">Site</div> <div class="div_var_name_container"> <div id="group_name_257_var_8" class="div_var_name" >variable 1</div> <div id="group_name_257_var_7" class="div_var_name" style="border-top:1px solid #000000;">variable 2</div> <div id="group_name_257_var_9" class="div_var_name" style="border-top:1px solid #000000;">variable 3</div> </div> <div class="div_var_value_container"> <div id="group_value_257_var_8" class="div_var_value" >0</div> <div id="group_value_257_var_7" class="div_var_value" style="border-top:1px solid #000000;">0</div> <div id="group_value_257_var_9" class="div_var_value" style="border-top:1px solid #000000;">0</div> </div> <div class="div_var_unit_container"> <div id="group_unit_257_var_8" class="div_var_unit" >N/A</div> <div id="group_unit_257_var_7" class="div_var_unit" style="border-top:1px solid #000000;">N/A</div> <div id="group_unit_257_var_9" class="div_var_unit" style="border-top:1px solid #000000;">N/A</div> </div> <div id="group_257_timestamp" class="div_timestamp" style="">-</div> </div> </div><div class="clearer"></div><div class="copyright">© Copyright</div><div id="div_last_update_time">-</div> </div> <iframe id="webmap_update" style="display:none;" width="0" height="0"></iframe></body> </html> The divs with class div_var_value, div_timestamp & div_last_update_time all get updated by the javascript function. The div "div_image_container" is the one that is causing this it seems, atleast if I change the position property for it from relative to static the values get updated correctly This is the page that updates the values: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Loader</title> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/> <script type="text/javascript"> <!-- window.onload = doLoad; function refresh() { //window.location.reload( false ); var _random_num = Math.floor(Math.random()*1100); window.location.search="?map_id=54&first_time=0&t="+_random_num; } var var_array = new Array(); var timestamp_array = new Array(); var_array[0] = Array('group_value_257_var_9','41.73',-1, 9, 0); var_array[1] = Array('group_value_257_var_7','62.48',-1, 7, 0); var_array[2] = Array('group_value_257_var_8','4.24',-1, 8, 0); var current_time = new Date(); var current_time_str = current_time.getHours(); current_time_str += ':'+current_time.getMinutes(); current_time_str += ':'+current_time.getSeconds(); timestamp_array[0] = Array('group_257_timestamp',current_time_str,'box_group_container_206',-1, -1); //timestamp_array[0] = Array('group_257_timestamp','11:33:16 23.Nov','box_group_container_257',-1, -1); window.parent.updateParent(var_array, timestamp_array); function doLoad() { setTimeout( "refresh()", 10*1000 ); } //--> </script> </head> <body> </body> </html> I edited the post and added a link to the webpage in question, I have also tested the webpage in internet explorer 7 and this error does not appear there. I have only seen this error in ie8 with compatibility turned on. If anybody has seen this before and has a fix, I would be very grateful. Thanks.

    Read the article

  • Passing data between android ListActivities in Java

    - by Will Janes
    I am new to Android! I am having a problem getting this code to work... Basically I Go from one list activity to another and pass the text from a list item through the intent of the activity to the new list view, then retrieve that text in the new list activity and then preform a http request based on value of that list item. Log Cat 04-05 17:47:32.370: E/AndroidRuntime(30135): FATAL EXCEPTION: main 04-05 17:47:32.370: E/AndroidRuntime(30135): java.lang.ClassCastException:android.widget.LinearLayout 04-05 17:47:32.370: E/AndroidRuntime(30135): at com.thickcrustdesigns.ufood.CatogPage$1.onItemClick(CatogPage.java:66) 04-05 17:47:32.370: E/AndroidRuntime(30135): at android.widget.AdapterView.performItemClick(AdapterView.java:284) 04-05 17:47:32.370: E/AndroidRuntime(30135): at android.widget.ListView.performItemClick(ListView.java:3731) 04-05 17:47:32.370: E/AndroidRuntime(30135): at android.widget.AbsListView$PerformClick.run(AbsListView.java:1959) 04-05 17:47:32.370: E/AndroidRuntime(30135): at android.os.Handler.handleCallback(Handler.java:587) 04-05 17:47:32.370: E/AndroidRuntime(30135): at android.os.Handler.dispatchMessage(Handler.java:92) 04-05 17:47:32.370: E/AndroidRuntime(30135): at android.os.Looper.loop(Looper.java:130) 04-05 17:47:32.370: E/AndroidRuntime(30135): at android.app.ActivityThread.main(ActivityThread.java:3691) 04-05 17:47:32.370: E/AndroidRuntime(30135): at java.lang.reflect.Method.invokeNative(Native Method) 04-05 17:47:32.370: E/AndroidRuntime(30135): at java.lang.reflect.Method.invoke(Method.java:507) 04-05 17:47:32.370: E/AndroidRuntime(30135): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:907) 04-05 17:47:32.370: E/AndroidRuntime(30135): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:665) 04-05 17:47:32.370: E/AndroidRuntime(30135): at dalvik.system.NativeStart.main(Native Method) ListActivity 1 package com.thickcrustdesigns.ufood; import java.util.ArrayList; import org.apache.http.NameValuePair; import org.apache.http.message.BasicNameValuePair; import org.json.JSONException; import org.json.JSONObject; import android.app.ListActivity; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.widget.AdapterView; import android.widget.AdapterView.OnItemClickListener; import android.widget.Button; import android.widget.ListView; import android.widget.TextView; public class CatogPage extends ListActivity { ListView listView1; Button btn_bk; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.definition_main); btn_bk = (Button) findViewById(R.id.btn_bk); listView1 = (ListView) findViewById(android.R.id.list); ArrayList<NameValuePair> nvp = new ArrayList<NameValuePair>(); nvp.add(new BasicNameValuePair("request", "categories")); ArrayList<JSONObject> jsondefs = Request.fetchData(this, nvp); String[] defs = new String[jsondefs.size()]; for (int i = 0; i < jsondefs.size(); i++) { try { defs[i] = jsondefs.get(i).getString("Name"); } catch (JSONException e) { // TODO Auto-generated catch block e.printStackTrace(); } } uFoodAdapter adapter = new uFoodAdapter(this, R.layout.definition_list, defs); listView1.setAdapter(adapter); ListView lv = getListView(); lv.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { TextView tv = (TextView) view; String p = tv.getText().toString(); Intent i = new Intent(getApplicationContext(), Results.class); i.putExtra("category", p); startActivity(i); } }); btn_bk.setOnClickListener(new View.OnClickListener() { public void onClick(View arg0) { Intent i = new Intent(getApplicationContext(), UFoodAppActivity.class); startActivity(i); } }); } } **ListActivity 2** package com.thickcrustdesigns.ufood; import java.util.ArrayList; import org.apache.http.NameValuePair; import org.apache.http.message.BasicNameValuePair; import org.json.JSONException; import org.json.JSONObject; import android.app.ListActivity; import android.os.Bundle; import android.widget.ListView; public class Results extends ListActivity { ListView listView1; enum Category { Chicken, Beef, Chinese, Cocktails, Curry, Deserts, Fish, ForOne { public String toString() { return "For One"; } }, Lamb, LightBites { public String toString() { return "Light Bites"; } }, Pasta, Pork, Vegetarian } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); this.setContentView(R.layout.definition_main); listView1 = (ListView) findViewById(android.R.id.list); Bundle data = getIntent().getExtras(); String category = data.getString("category"); Category cat = Category.valueOf(category); String value = null; switch (cat) { case Chicken: value = "Chicken"; break; case Beef: value = "Beef"; break; case Chinese: value = "Chinese"; break; case Cocktails: value = "Cocktails"; break; case Curry: value = "Curry"; break; case Deserts: value = "Deserts"; break; case Fish: value = "Fish"; break; case ForOne: value = "ForOne"; break; case Lamb: value = "Lamb"; break; case LightBites: value = "LightBites"; break; case Pasta: value = "Pasta"; break; case Pork: value = "Pork"; break; case Vegetarian: value = "Vegetarian"; } ArrayList<NameValuePair> nvp = new ArrayList<NameValuePair>(); nvp.add(new BasicNameValuePair("request", "category")); nvp.add(new BasicNameValuePair("cat", value)); ArrayList<JSONObject> jsondefs = Request.fetchData(this, nvp); String[] defs = new String[jsondefs.size()]; for (int i = 0; i < jsondefs.size(); i++) { try { defs[i] = jsondefs.get(i).getString("Name"); } catch (JSONException e) { // TODO Auto-generated catch block e.printStackTrace(); } } uFoodAdapter adapter = new uFoodAdapter(this, R.layout.definition_list, defs); listView1.setAdapter(adapter); } } Request package com.thickcrustdesigns.ufood; import java.io.BufferedReader; import java.io.InputStream; import java.io.InputStreamReader; import java.util.ArrayList; import org.apache.http.HttpEntity; import org.apache.http.HttpResponse; import org.apache.http.NameValuePair; import org.apache.http.client.HttpClient; import org.apache.http.client.entity.UrlEncodedFormEntity; import org.apache.http.client.methods.HttpPost; import org.apache.http.impl.client.DefaultHttpClient; import org.json.JSONArray; import org.json.JSONObject; import android.content.Context; import android.util.Log; import android.widget.Toast; public class Request { @SuppressWarnings("null") public static ArrayList<JSONObject> fetchData(Context context, ArrayList<NameValuePair> nvp) { ArrayList<JSONObject> listItems = new ArrayList<JSONObject>(); InputStream is = null; try { HttpClient httpclient = new DefaultHttpClient(); HttpPost httppost = new HttpPost( "http://co350-11d.projects02.glos.ac.uk/php/database.php"); httppost.setEntity(new UrlEncodedFormEntity(nvp)); HttpResponse response = httpclient.execute(httppost); HttpEntity entity = response.getEntity(); is = entity.getContent(); } catch (Exception e) { Log.e("log_tag", "Error in http connection" + e.toString()); } // convert response to string String result = ""; try { BufferedReader reader = new BufferedReader(new InputStreamReader( is, "iso-8859-1"), 8); InputStream stream = null; StringBuilder sb = null; while ((result = reader.readLine()) != null) { sb.append(result + "\n"); } stream.close(); result = sb.toString(); } catch (Exception e) { Log.e("log_tag", "Error converting result " + e.toString()); } try { JSONArray jArray = new JSONArray(result); for (int i = 0; i < jArray.length(); i++) { JSONObject jo = jArray.getJSONObject(i); listItems.add(jo); } } catch (Exception e) { Toast.makeText(context.getApplicationContext(), "None Found!", Toast.LENGTH_LONG).show(); } return listItems; } } Any help would be grateful! Many Thanks EDIT Sorry very tired so missed out my 2nd ListActivity package com.thickcrustdesigns.ufood; import java.util.ArrayList; import org.apache.http.NameValuePair; import org.apache.http.message.BasicNameValuePair; import org.json.JSONException; import org.json.JSONObject; import android.app.ListActivity; import android.os.Bundle; import android.widget.ListView; public class Results extends ListActivity { ListView listView1; enum Category { Chicken, Beef, Chinese, Cocktails, Curry, Deserts, Fish, ForOne { public String toString() { return "For One"; } }, Lamb, LightBites { public String toString() { return "Light Bites"; } }, Pasta, Pork, Vegetarian } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); this.setContentView(R.layout.definition_main); listView1 = (ListView) findViewById(android.R.id.list); Bundle data = getIntent().getExtras(); String category = data.getString("category"); Category cat = Category.valueOf(category); String value = null; switch (cat) { case Chicken: value = "Chicken"; break; case Beef: value = "Beef"; break; case Chinese: value = "Chinese"; break; case Cocktails: value = "Cocktails"; break; case Curry: value = "Curry"; break; case Deserts: value = "Deserts"; break; case Fish: value = "Fish"; break; case ForOne: value = "ForOne"; break; case Lamb: value = "Lamb"; break; case LightBites: value = "LightBites"; break; case Pasta: value = "Pasta"; break; case Pork: value = "Pork"; break; case Vegetarian: value = "Vegetarian"; } ArrayList<NameValuePair> nvp = new ArrayList<NameValuePair>(); nvp.add(new BasicNameValuePair("request", "category")); nvp.add(new BasicNameValuePair("cat", value)); ArrayList<JSONObject> jsondefs = Request.fetchData(this, nvp); String[] defs = new String[jsondefs.size()]; for (int i = 0; i < jsondefs.size(); i++) { try { defs[i] = jsondefs.get(i).getString("Name"); } catch (JSONException e) { // TODO Auto-generated catch block e.printStackTrace(); } } uFoodAdapter adapter = new uFoodAdapter(this, R.layout.definition_list, defs); listView1.setAdapter(adapter); } } Sorry again! Cheers guys!

    Read the article

  • Issue with my wordpress functions.php script

    - by iMayne
    Hello peeps. Im having an issues when activating my theme in wordpress. I got this error message: "Parse error: syntax error, unexpected $end in C:\xampp\htdocs\xampp\wordpress\wp-content\themes\xit\functions.php on line 223". Whats wrong, I totally dont understand. The script of the php is: <?php if ( function_exists('register_sidebar') ) register_sidebar(array( 'before_widget' => '', 'after_widget' => '', 'before_title' => '<h2>', 'after_title' => '</h2>', )); function content($num) { $theContent = get_the_content(); $output = preg_replace('/<img[^>]+./','', $theContent); $limit = $num+1; $content = explode(' ', $output, $limit); array_pop($content); $content = implode(" ",$content)."..."; echo $content; } function post_is_in_descendant_category( $cats, $_post = null ) { foreach ( (array) $cats as $cat ) { // get_term_children() accepts integer ID only $descendants = get_term_children( (int) $cat, 'category'); if ( $descendants && in_category( $descendants, $_post ) ) return true; } return false; } //custom comments function mytheme_comment($comment, $args, $depth) { $GLOBALS['comment'] = $comment; ?> <li <?php comment_class(); ?> id="li-comment-<?php comment_ID() ?>"> <div id="comment-<?php comment_ID(); ?>"> <div class="comment-author vcard"> <div class="comment-meta commentmetadata"> <?php echo get_avatar($comment,$size='32',$default='http://www.gravatar.com/avatar/61a58ec1c1fba116f8424035089b7c71?s=32&d=&r=G' ); ?> <?php printf(__('%1$s at %2$s'), get_comment_date(), get_comment_time()) ?> <br /><?php printf(__('<strong>%s</strong> says:'), get_comment_author_link()) ?><?php edit_comment_link(__('(Edit)'),' ','') ?></div> </div> <?php if ($comment->comment_approved == '0') : ?> <em><?php _e('Your comment is awaiting moderation.') ?></em> <br /> <?php endif; ?> <div class="text"><?php comment_text() ?></div> <div class="reply"> <?php comment_reply_link(array_merge( $args, array('depth' => $depth, 'max_depth' => $args['max_depth']))) ?> </div> </div> <?php } add_action('admin_menu', 'xit_theme_page'); function xit_theme_page () { if ( count($_POST) > 0 && isset($_POST['xit_settings']) ) { $options = array ( 'style','logo_img','logo_alt','logo_txt', 'logo_tagline', 'tagline_width', 'contact_email','ads', 'advertise_page', 'twitter_link', 'facebook_link', 'flickr', 'about_tit', 'about_txt', 'analytics'); foreach ( $options as $opt ) { delete_option ( 'xit_'.$opt, $_POST[$opt] ); add_option ( 'xit_'.$opt, $_POST[$opt] ); } } add_theme_page(__('Xit Options'), __('Xit Options'), 'edit_themes', basename(__FILE__), 'xit_settings'); } function xit_settings () {?> <div class="wrap"> <h2>XIT Options Panel</h2> <form method="post" action=""> <table class="form-table"> <!-- General settings --> <tr> <th colspan="2"><strong>General Settings</strong></th> </tr> <tr valign="top"> <th scope="row"><label for="style">Theme Color Scheme</label></th> <td> <select name="style" id="style"> <option value="pink.css" <?php if(get_option('xit_style') == 'pink.css'){?>selected="selected"<?php }?>>pink.css</option> <option value="blue.css" <?php if(get_option('xit_style') == 'blue.css'){?>selected="selected"<?php }?>>blue.css</option> <option value="orange.css" <?php if(get_option('xit_style') == 'orange.css'){?>selected="selected"<?php }?>>orange.css</option> </select> </td> </tr> <tr valign="top"> <th scope="row"><label for="logo_img">Logo image (full path to image)</label></th> <td> <input name="logo_img" type="text" id="logo_img" value="<?php echo get_option('xit_logo_img'); ?>" class="regular-text" /> </td> </tr> <tr valign="top"> <th scope="row"><label for="logo_alt">Logo image ALT text</label></th> <td> <input name="logo_alt" type="text" id="logo_alt" value="<?php echo get_option('xit_logo_alt'); ?>" class="regular-text" /> </td> </tr> <tr valign="top"> <th scope="row"><label for="logo_txt">Text logo</label></th> <td> <input name="logo_txt" type="text" id="logo_txt" value="<?php echo get_option('xit_logo_txt'); ?>" class="regular-text" /> <br /><em>Leave this empty if you entered an image as logo</em> </td> </tr> <tr valign="top"> <th scope="row"><label for="logo_tagline">Logo Tag Line</label></th> <td> <input name="logo_tagline" type="text" id="logo_tagline" value="<?php echo get_option('xit_logo_tagline'); ?>" class="regular-text" /> </td> </tr> <tr valign="top"> <th scope="row"><label for="tagline_width">Tag Line Box Width (px)</label><br /><em style="font-size:11px">Default width: 300px</em></th> <td> <input name="tagline_width" type="text" id="tagline_width" value="<?php echo get_option('xit_tagline_width'); ?>" class="regular-text" /> </td> </tr> <tr valign="top"> <th scope="row"><label for="contact_email">Email Address for Contact Form</label></th> <td> <input name="contact_email" type="text" id="contact_email" value="<?php echo get_option('xit_contact_email'); ?>" class="regular-text" /> </td> </tr> <tr valign="top"> <th scope="row"><label for="twitter_link">Twitter link</label></th> <td> <input name="twitter_link" type="text" id="twitter_link" value="<?php echo get_option('xit_twitter_link'); ?>" class="regular-text" /> </td> </tr> <tr valign="top"> <th scope="row"><label for="facebook_link">Facebook link</label></th> <td> <input name="facebook_link" type="text" id="facebook_link" value="<?php echo get_option('xit_facebook_link'); ?>" class="regular-text" /> </td> </tr> <tr valign="top"> <th scope="row"><label for="flickr">Flickr Photostream</label></th> <td> <select name="flickr" id="flickr"> <option value="yes" <?php if(get_option('xit_flickr') == 'yes'){?>selected="selected"<?php }?>>Yes</option> <option value="no" <?php if(get_option('xit_flickr') == 'no'){?>selected="selected"<?php }?>>No</option> </select> <br /><em>Make sure you have FlickrRSS plugin activated if you choose to enable Flickr Photostream</em> </td> </tr> <!-- Sidebar ABout Box--> <tr> <th colspan="2"><strong>Sidebar About Box</strong></th> </tr> <tr valign="top"> <th scope="row"><label for="about_tit">Title</label></th> <td> <input name="about_tit" type="text" id="about_tit" value="<?php echo get_option('xit_about_tit'); ?>" class="regular-text" /> </td> </tr> <tr valign="top"> <th scope="row"><label for="about_txt">Text</label></th> <td> <textarea cols="60" rows="5" name="about_txt" type="text" id="about_txt" class="regular-text" /><?php echo get_option('xit_about_txt'); ?></textarea> </td> </tr> <!-- Ads Box Settings --> <tr> <th colspan="2"><strong>Ads Box Settings</strong></th> </tr> <tr> <th><label for="ads">Ads Section Enabled:</label></th> <td> <select name="ads" id="ads"> <option value="yes" <?php if(get_option('xit_ads') == 'yes'){?>selected="selected"<?php }?>>Yes</option> <option value="no" <?php if(get_option('xit_ads') == 'no'){?>selected="selected"<?php }?>>No</option> </select> <br /><em>Make sure you have AdMinister plugin activated and have the position "Sidebar" created within the plugin.</em> </td> </tr> <tr valign="top"> <th scope="row"><label for="advertise_page">Advertise Page</label></th> <td> <?php wp_dropdown_pages("name=advertise_page&show_option_none=".__('- Select -')."&selected=" .get_option('xit_advertise_page')); ?> </td> </tr> <!-- Google Analytics --> <tr> <th><label for="ads">Google Analytics code:</label></th> <td> <textarea name="analytics" id="analytics" rows="7" cols="70" style="font-size:11px;"><?php echo stripslashes(get_option('xit_analytics')); ?></textarea> </td> </tr> </table> <p class="submit"> <input type="submit" name="Submit" class="button-primary" value="Save Changes" /> <input type="hidden" name="xit_settings" value="save" style="display:none;" /> </p> </form> </div> <? }?> <?php function get_first_image() { global $post, $posts; $first_img = ''; ob_start(); ob_end_clean(); $output = preg_match_all('/<img.+src=[\'"]([^\'"]+)[\'"].*>/i', $post->post_content, $matches); $first_img = $matches [1] [0]; if(empty($first_img)){ //Defines a default image $first_img = "/images/default.jpg"; } return $first_img; } ?> The last line is line 223.

    Read the article

  • exchange web service C# code send email from home

    - by KK
    Is it possible to write C# code as below and send email using my home network? I have a valid user name and password on that exchange server. Is there any configuration that I can set to achieve this? BTW this code blow works when I run it within office network. I want this code to work when run from any network. String cMSExchangeWebServiceURL = (String)System.Configuration.ConfigurationSettings.AppSettings["MSExchangeWebServiceURL"]; String cEmail = (String)System.Configuration.ConfigurationSettings.AppSettings["Cemail"]; String cPassword = (String)System.Configuration.ConfigurationSettings.AppSettings["Cpassword"]; String cTo = (String)System.Configuration.ConfigurationSettings.AppSettings["CTo"]; ExchangeServiceBinding esb = new ExchangeServiceBinding(); esb.Timeout = 1800000; esb.AllowAutoRedirect = true; esb.UseDefaultCredentials = false; esb.Credentials = new NetworkCredential(cEmail, cPassword); esb.Url = cMSExchangeWebServiceURL; ServicePointManager.ServerCertificateValidationCallback += delegate(object sender1, X509Certificate certificate, X509Chain chain, SslPolicyErrors sslPolicyErrors) { return true; }; // Create a CreateItem request object CreateItemType request = new CreateItemType(); // Setup the request: // Indicate that we only want to send the message. No copy will be saved. request.MessageDisposition = MessageDispositionType.SendOnly; request.MessageDispositionSpecified = true; // Create a message object and set its properties MessageType message = new MessageType(); message.Subject = subject; message.Body = new TestOutgoingEmailServer.com.cogniti.mail1.BodyType(); message.Body.BodyType1 = BodyTypeType.HTML; message.Body.Value = body; message.ToRecipients = new EmailAddressType[3]; message.ToRecipients[0] = new EmailAddressType(); //message.ToRecipients[1] = new EmailAddressType(); //message.ToRecipients[2] = new EmailAddressType(); message.ToRecipients[0].EmailAddress = "[email protected]"; message.ToRecipients[0].RoutingType = "SMTP"; //message.CcRecipients = new EmailAddressType[1]; //message.CcRecipients[0] = new EmailAddressType(); //message.CcRecipients[0].EmailAddress = toEmailAddress.ElementAt(1).ToString(); //message.CcRecipients[0].RoutingType = "SMTP"; //There are some more properties in MessageType object //you can set all according to your requirement // Construct the array of items to send request.Items = new NonEmptyArrayOfAllItemsType(); request.Items.Items = new ItemType[1]; request.Items.Items[0] = message; // Call the CreateItem EWS method. CreateItemResponseType response = esb.CreateItem(request);

    Read the article

  • Metro: Creating an IndexedDbDataSource for WinJS

    - by Stephen.Walther
    The goal of this blog entry is to describe how you can create custom data sources which you can use with the controls in the WinJS library. In particular, I explain how you can create an IndexedDbDataSource which you can use to store and retrieve data from an IndexedDB database. If you want to skip ahead, and ignore all of the fascinating content in-between, I’ve included the complete code for the IndexedDbDataSource at the very bottom of this blog entry. What is IndexedDB? IndexedDB is a database in the browser. You can use the IndexedDB API with all modern browsers including Firefox, Chrome, and Internet Explorer 10. And, of course, you can use IndexedDB with Metro style apps written with JavaScript. If you need to persist data in a Metro style app written with JavaScript then IndexedDB is a good option. Each Metro app can only interact with its own IndexedDB databases. And, IndexedDB provides you with transactions, indices, and cursors – the elements of any modern database. An IndexedDB database might be different than the type of database that you normally use. An IndexedDB database is an object-oriented database and not a relational database. Instead of storing data in tables, you store data in object stores. You store JavaScript objects in an IndexedDB object store. You create new IndexedDB object stores by handling the upgradeneeded event when you attempt to open a connection to an IndexedDB database. For example, here’s how you would both open a connection to an existing database named TasksDB and create the TasksDB database when it does not already exist: var reqOpen = window.indexedDB.open(“TasksDB”, 2); reqOpen.onupgradeneeded = function (evt) { var newDB = evt.target.result; newDB.createObjectStore("tasks", { keyPath: "id", autoIncrement: true }); }; reqOpen.onsuccess = function () { var db = reqOpen.result; // Do something with db }; When you call window.indexedDB.open(), and the database does not already exist, then the upgradeneeded event is raised. In the code above, the upgradeneeded handler creates a new object store named tasks. The new object store has an auto-increment column named id which acts as the primary key column. If the database already exists with the right version, and you call window.indexedDB.open(), then the success event is raised. At that point, you have an open connection to the existing database and you can start doing something with the database. You use asynchronous methods to interact with an IndexedDB database. For example, the following code illustrates how you would add a new object to the tasks object store: var transaction = db.transaction(“tasks”, “readwrite”); var reqAdd = transaction.objectStore(“tasks”).add({ name: “Feed the dog” }); reqAdd.onsuccess = function() { // Tasks added successfully }; The code above creates a new database transaction, adds a new task to the tasks object store, and handles the success event. If the new task gets added successfully then the success event is raised. Creating a WinJS IndexedDbDataSource The most powerful control in the WinJS library is the ListView control. This is the control that you use to display a collection of items. If you want to display data with a ListView control, you need to bind the control to a data source. The WinJS library includes two objects which you can use as a data source: the List object and the StorageDataSource object. The List object enables you to represent a JavaScript array as a data source and the StorageDataSource enables you to represent the file system as a data source. If you want to bind an IndexedDB database to a ListView then you have a choice. You can either dump the items from the IndexedDB database into a List object or you can create a custom data source. I explored the first approach in a previous blog entry. In this blog entry, I explain how you can create a custom IndexedDB data source. Implementing the IListDataSource Interface You create a custom data source by implementing the IListDataSource interface. This interface contains the contract for the methods which the ListView needs to interact with a data source. The easiest way to implement the IListDataSource interface is to derive a new object from the base VirtualizedDataSource object. The VirtualizedDataSource object requires a data adapter which implements the IListDataAdapter interface. Yes, because of the number of objects involved, this is a little confusing. Your code ends up looking something like this: var IndexedDbDataSource = WinJS.Class.derive( WinJS.UI.VirtualizedDataSource, function (dbName, dbVersion, objectStoreName, upgrade, error) { this._adapter = new IndexedDbDataAdapter(dbName, dbVersion, objectStoreName, upgrade, error); this._baseDataSourceConstructor(this._adapter); }, { nuke: function () { this._adapter.nuke(); }, remove: function (key) { this._adapter.removeInternal(key); } } ); The code above is used to create a new class named IndexedDbDataSource which derives from the base VirtualizedDataSource class. In the constructor for the new class, the base class _baseDataSourceConstructor() method is called. A data adapter is passed to the _baseDataSourceConstructor() method. The code above creates a new method exposed by the IndexedDbDataSource named nuke(). The nuke() method deletes all of the objects from an object store. The code above also overrides a method named remove(). Our derived remove() method accepts any type of key and removes the matching item from the object store. Almost all of the work of creating a custom data source goes into building the data adapter class. The data adapter class implements the IListDataAdapter interface which contains the following methods: · change() · getCount() · insertAfter() · insertAtEnd() · insertAtStart() · insertBefore() · itemsFromDescription() · itemsFromEnd() · itemsFromIndex() · itemsFromKey() · itemsFromStart() · itemSignature() · moveAfter() · moveBefore() · moveToEnd() · moveToStart() · remove() · setNotificationHandler() · compareByIdentity Fortunately, you are not required to implement all of these methods. You only need to implement the methods that you actually need. In the case of the IndexedDbDataSource, I implemented the getCount(), itemsFromIndex(), insertAtEnd(), and remove() methods. If you are creating a read-only data source then you really only need to implement the getCount() and itemsFromIndex() methods. Implementing the getCount() Method The getCount() method returns the total number of items from the data source. So, if you are storing 10,000 items in an object store then this method would return the value 10,000. Here’s how I implemented the getCount() method: getCount: function () { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore().then(function (store) { var reqCount = store.count(); reqCount.onerror = that._error; reqCount.onsuccess = function (evt) { complete(evt.target.result); }; }); }); } The first thing that you should notice is that the getCount() method returns a WinJS promise. This is a requirement. The getCount() method is asynchronous which is a good thing because all of the IndexedDB methods (at least the methods implemented in current browsers) are also asynchronous. The code above retrieves an object store and then uses the IndexedDB count() method to get a count of the items in the object store. The value is returned from the promise by calling complete(). Implementing the itemsFromIndex method When a ListView displays its items, it calls the itemsFromIndex() method. By default, it calls this method multiple times to get different ranges of items. Three parameters are passed to the itemsFromIndex() method: the requestIndex, countBefore, and countAfter parameters. The requestIndex indicates the index of the item from the database to show. The countBefore and countAfter parameters represent hints. These are integer values which represent the number of items before and after the requestIndex to retrieve. Again, these are only hints and you can return as many items before and after the request index as you please. Here’s how I implemented the itemsFromIndex method: itemsFromIndex: function (requestIndex, countBefore, countAfter) { var that = this; return new WinJS.Promise(function (complete, error) { that.getCount().then(function (count) { if (requestIndex >= count) { return WinJS.Promise.wrapError(new WinJS.ErrorFromName(WinJS.UI.FetchError.doesNotExist)); } var startIndex = Math.max(0, requestIndex - countBefore); var endIndex = Math.min(count, requestIndex + countAfter + 1); that._getObjectStore().then(function (store) { var index = 0; var items = []; var req = store.openCursor(); req.onerror = that._error; req.onsuccess = function (evt) { var cursor = evt.target.result; if (index < startIndex) { index = startIndex; cursor.advance(startIndex); return; } if (cursor && index < endIndex) { index++; items.push({ key: cursor.value[store.keyPath].toString(), data: cursor.value }); cursor.continue(); return; } results = { items: items, offset: requestIndex - startIndex, totalCount: count }; complete(results); }; }); }); }); } In the code above, a cursor is used to iterate through the objects in an object store. You fetch the next item in the cursor by calling either the cursor.continue() or cursor.advance() method. The continue() method moves forward by one object and the advance() method moves forward a specified number of objects. Each time you call continue() or advance(), the success event is raised again. If the cursor is null then you know that you have reached the end of the cursor and you can return the results. Some things to be careful about here. First, the return value from the itemsFromIndex() method must implement the IFetchResult interface. In particular, you must return an object which has an items, offset, and totalCount property. Second, each item in the items array must implement the IListItem interface. Each item should have a key and a data property. Implementing the insertAtEnd() Method When creating the IndexedDbDataSource, I wanted to go beyond creating a simple read-only data source and support inserting and deleting objects. If you want to support adding new items with your data source then you need to implement the insertAtEnd() method. Here’s how I implemented the insertAtEnd() method for the IndexedDbDataSource: insertAtEnd:function(unused, data) { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function(store) { var reqAdd = store.add(data); reqAdd.onerror = that._error; reqAdd.onsuccess = function (evt) { var reqGet = store.get(evt.target.result); reqGet.onerror = that._error; reqGet.onsuccess = function (evt) { var newItem = { key:evt.target.result[store.keyPath].toString(), data:evt.target.result } complete(newItem); }; }; }); }); } When implementing the insertAtEnd() method, you need to be careful to return an object which implements the IItem interface. In particular, you should return an object that has a key and a data property. The key must be a string and it uniquely represents the new item added to the data source. The value of the data property represents the new item itself. Implementing the remove() Method Finally, you use the remove() method to remove an item from the data source. You call the remove() method with the key of the item which you want to remove. Implementing the remove() method in the case of the IndexedDbDataSource was a little tricky. The problem is that an IndexedDB object store uses an integer key and the VirtualizedDataSource requires a string key. For that reason, I needed to override the remove() method in the derived IndexedDbDataSource class like this: var IndexedDbDataSource = WinJS.Class.derive( WinJS.UI.VirtualizedDataSource, function (dbName, dbVersion, objectStoreName, upgrade, error) { this._adapter = new IndexedDbDataAdapter(dbName, dbVersion, objectStoreName, upgrade, error); this._baseDataSourceConstructor(this._adapter); }, { nuke: function () { this._adapter.nuke(); }, remove: function (key) { this._adapter.removeInternal(key); } } ); When you call remove(), you end up calling a method of the IndexedDbDataAdapter named removeInternal() . Here’s what the removeInternal() method looks like: setNotificationHandler: function (notificationHandler) { this._notificationHandler = notificationHandler; }, removeInternal: function(key) { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function (store) { var reqDelete = store.delete (key); reqDelete.onerror = that._error; reqDelete.onsuccess = function (evt) { that._notificationHandler.removed(key.toString()); complete(); }; }); }); } The removeInternal() method calls the IndexedDB delete() method to delete an item from the object store. If the item is deleted successfully then the _notificationHandler.remove() method is called. Because we are not implementing the standard IListDataAdapter remove() method, we need to notify the data source (and the ListView control bound to the data source) that an item has been removed. The way that you notify the data source is by calling the _notificationHandler.remove() method. Notice that we get the _notificationHandler in the code above by implementing another method in the IListDataAdapter interface: the setNotificationHandler() method. You can raise the following types of notifications using the _notificationHandler: · beginNotifications() · changed() · endNotifications() · inserted() · invalidateAll() · moved() · removed() · reload() These methods are all part of the IListDataNotificationHandler interface in the WinJS library. Implementing the nuke() Method I wanted to implement a method which would remove all of the items from an object store. Therefore, I created a method named nuke() which calls the IndexedDB clear() method: nuke: function () { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function (store) { var reqClear = store.clear(); reqClear.onerror = that._error; reqClear.onsuccess = function (evt) { that._notificationHandler.reload(); complete(); }; }); }); } Notice that the nuke() method calls the _notificationHandler.reload() method to notify the ListView to reload all of the items from its data source. Because we are implementing a custom method here, we need to use the _notificationHandler to send an update. Using the IndexedDbDataSource To illustrate how you can use the IndexedDbDataSource, I created a simple task list app. You can add new tasks, delete existing tasks, and nuke all of the tasks. You delete an item by selecting an item (swipe or right-click) and clicking the Delete button. Here’s the HTML page which contains the ListView, the form for adding new tasks, and the buttons for deleting and nuking tasks: <!DOCTYPE html> <html> <head> <meta charset="utf-8" /> <title>DataSources</title> <!-- WinJS references --> <link href="//Microsoft.WinJS.1.0.RC/css/ui-dark.css" rel="stylesheet" /> <script src="//Microsoft.WinJS.1.0.RC/js/base.js"></script> <script src="//Microsoft.WinJS.1.0.RC/js/ui.js"></script> <!-- DataSources references --> <link href="indexedDb.css" rel="stylesheet" /> <script type="text/javascript" src="indexedDbDataSource.js"></script> <script src="indexedDb.js"></script> </head> <body> <div id="tmplTask" data-win-control="WinJS.Binding.Template"> <div class="taskItem"> Id: <span data-win-bind="innerText:id"></span> <br /><br /> Name: <span data-win-bind="innerText:name"></span> </div> </div> <div id="lvTasks" data-win-control="WinJS.UI.ListView" data-win-options="{ itemTemplate: select('#tmplTask'), selectionMode: 'single' }"></div> <form id="frmAdd"> <fieldset> <legend>Add Task</legend> <label>New Task</label> <input id="inputTaskName" required /> <button>Add</button> </fieldset> </form> <button id="btnNuke">Nuke</button> <button id="btnDelete">Delete</button> </body> </html> And here is the JavaScript code for the TaskList app: /// <reference path="//Microsoft.WinJS.1.0.RC/js/base.js" /> /// <reference path="//Microsoft.WinJS.1.0.RC/js/ui.js" /> function init() { WinJS.UI.processAll().done(function () { var lvTasks = document.getElementById("lvTasks").winControl; // Bind the ListView to its data source var tasksDataSource = new DataSources.IndexedDbDataSource("TasksDB", 1, "tasks", upgrade); lvTasks.itemDataSource = tasksDataSource; // Wire-up Add, Delete, Nuke buttons document.getElementById("frmAdd").addEventListener("submit", function (evt) { evt.preventDefault(); tasksDataSource.beginEdits(); tasksDataSource.insertAtEnd(null, { name: document.getElementById("inputTaskName").value }).done(function (newItem) { tasksDataSource.endEdits(); document.getElementById("frmAdd").reset(); lvTasks.ensureVisible(newItem.index); }); }); document.getElementById("btnDelete").addEventListener("click", function () { if (lvTasks.selection.count() == 1) { lvTasks.selection.getItems().done(function (items) { tasksDataSource.remove(items[0].data.id); }); } }); document.getElementById("btnNuke").addEventListener("click", function () { tasksDataSource.nuke(); }); // This method is called to initialize the IndexedDb database function upgrade(evt) { var newDB = evt.target.result; newDB.createObjectStore("tasks", { keyPath: "id", autoIncrement: true }); } }); } document.addEventListener("DOMContentLoaded", init); The IndexedDbDataSource is created and bound to the ListView control with the following two lines of code: var tasksDataSource = new DataSources.IndexedDbDataSource("TasksDB", 1, "tasks", upgrade); lvTasks.itemDataSource = tasksDataSource; The IndexedDbDataSource is created with four parameters: the name of the database to create, the version of the database to create, the name of the object store to create, and a function which contains code to initialize the new database. The upgrade function creates a new object store named tasks with an auto-increment property named id: function upgrade(evt) { var newDB = evt.target.result; newDB.createObjectStore("tasks", { keyPath: "id", autoIncrement: true }); } The Complete Code for the IndexedDbDataSource Here’s the complete code for the IndexedDbDataSource: (function () { /************************************************ * The IndexedDBDataAdapter enables you to work * with a HTML5 IndexedDB database. *************************************************/ var IndexedDbDataAdapter = WinJS.Class.define( function (dbName, dbVersion, objectStoreName, upgrade, error) { this._dbName = dbName; // database name this._dbVersion = dbVersion; // database version this._objectStoreName = objectStoreName; // object store name this._upgrade = upgrade; // database upgrade script this._error = error || function (evt) { console.log(evt.message); }; }, { /******************************************* * IListDataAdapter Interface Methods ********************************************/ getCount: function () { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore().then(function (store) { var reqCount = store.count(); reqCount.onerror = that._error; reqCount.onsuccess = function (evt) { complete(evt.target.result); }; }); }); }, itemsFromIndex: function (requestIndex, countBefore, countAfter) { var that = this; return new WinJS.Promise(function (complete, error) { that.getCount().then(function (count) { if (requestIndex >= count) { return WinJS.Promise.wrapError(new WinJS.ErrorFromName(WinJS.UI.FetchError.doesNotExist)); } var startIndex = Math.max(0, requestIndex - countBefore); var endIndex = Math.min(count, requestIndex + countAfter + 1); that._getObjectStore().then(function (store) { var index = 0; var items = []; var req = store.openCursor(); req.onerror = that._error; req.onsuccess = function (evt) { var cursor = evt.target.result; if (index < startIndex) { index = startIndex; cursor.advance(startIndex); return; } if (cursor && index < endIndex) { index++; items.push({ key: cursor.value[store.keyPath].toString(), data: cursor.value }); cursor.continue(); return; } results = { items: items, offset: requestIndex - startIndex, totalCount: count }; complete(results); }; }); }); }); }, insertAtEnd:function(unused, data) { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function(store) { var reqAdd = store.add(data); reqAdd.onerror = that._error; reqAdd.onsuccess = function (evt) { var reqGet = store.get(evt.target.result); reqGet.onerror = that._error; reqGet.onsuccess = function (evt) { var newItem = { key:evt.target.result[store.keyPath].toString(), data:evt.target.result } complete(newItem); }; }; }); }); }, setNotificationHandler: function (notificationHandler) { this._notificationHandler = notificationHandler; }, /***************************************** * IndexedDbDataSource Method ******************************************/ removeInternal: function(key) { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function (store) { var reqDelete = store.delete (key); reqDelete.onerror = that._error; reqDelete.onsuccess = function (evt) { that._notificationHandler.removed(key.toString()); complete(); }; }); }); }, nuke: function () { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function (store) { var reqClear = store.clear(); reqClear.onerror = that._error; reqClear.onsuccess = function (evt) { that._notificationHandler.reload(); complete(); }; }); }); }, /******************************************* * Private Methods ********************************************/ _ensureDbOpen: function () { var that = this; // Try to get cached Db if (that._cachedDb) { return WinJS.Promise.wrap(that._cachedDb); } // Otherwise, open the database return new WinJS.Promise(function (complete, error, progress) { var reqOpen = window.indexedDB.open(that._dbName, that._dbVersion); reqOpen.onerror = function (evt) { error(); }; reqOpen.onupgradeneeded = function (evt) { that._upgrade(evt); that._notificationHandler.invalidateAll(); }; reqOpen.onsuccess = function () { that._cachedDb = reqOpen.result; complete(that._cachedDb); }; }); }, _getObjectStore: function (type) { type = type || "readonly"; var that = this; return new WinJS.Promise(function (complete, error) { that._ensureDbOpen().then(function (db) { var transaction = db.transaction(that._objectStoreName, type); complete(transaction.objectStore(that._objectStoreName)); }); }); }, _get: function (key) { return new WinJS.Promise(function (complete, error) { that._getObjectStore().done(function (store) { var reqGet = store.get(key); reqGet.onerror = that._error; reqGet.onsuccess = function (item) { complete(item); }; }); }); } } ); var IndexedDbDataSource = WinJS.Class.derive( WinJS.UI.VirtualizedDataSource, function (dbName, dbVersion, objectStoreName, upgrade, error) { this._adapter = new IndexedDbDataAdapter(dbName, dbVersion, objectStoreName, upgrade, error); this._baseDataSourceConstructor(this._adapter); }, { nuke: function () { this._adapter.nuke(); }, remove: function (key) { this._adapter.removeInternal(key); } } ); WinJS.Namespace.define("DataSources", { IndexedDbDataSource: IndexedDbDataSource }); })(); Summary In this blog post, I provided an overview of how you can create a new data source which you can use with the WinJS library. I described how you can create an IndexedDbDataSource which you can use to bind a ListView control to an IndexedDB database. While describing how you can create a custom data source, I explained how you can implement the IListDataAdapter interface. You also learned how to raise notifications — such as a removed or invalidateAll notification — by taking advantage of the methods of the IListDataNotificationHandler interface.

    Read the article

  • Emails from Google Apps to custom SMTP server delayed by 1 hour consistently

    - by vimalk
    The outgoing mails from Google Apps/Gmail to our own custom SMTP server are getting delayed by 1 hour consistently. mxtoolbox.com diagnostics of our custom SMTP server are looking OK. Our custom SMTP server is receiving emails from other sources (yahoo, hotmail etc.) on time. Looking at the SMTP logs show a delay in a google intermediate SMTP server. Received: by qwi2 with SMTP id 2so1989393qwi.3 for <[email protected]>; Thu, 27 Jan 2011 03:54:23 -0800 (PST) MIME-Version: 1.0 Received: by 10.224.19.203 with SMTP id c11mr1587082qab.170.1296125657457; Thu, 27 Jan 2011 02:54:17 -0800 (PST) This setup has been working fine for a year though our custom email server was missing a reverse DNS entry and SPF records. Thinking that this could be the cause of the issue, we added these entries a week ago. But the issue still persists. Here are are more details: We are using Google Apps to host our primary domain email (say: mydomain.com) The custom SMTP server (say: s1.mydomain.com) hosts our subdomain (say: sub.mydomain.com) This is how the email log looks from [email protected] to [email protected] Return-Path: [email protected] Received: from localhost.localdomain (LHLO s1.mydomain.com) (127.0.0.1) by s1.mydomain.com with LMTP; Thu, 27 Jan 2011 17:24:28 +0530 (IST) Received: from localhost (localhost.localdomain [127.0.0.1]) by s1.mydomain.com (Postfix) with ESMTP id 605116A6565 for <[email protected]>; Thu, 27 Jan 2011 17:24:28 +0530 (IST) X-Virus-Scanned: amavisd-new at sub.mydomain.com X-Spam-Flag: NO X-Spam-Score: 2.984 X-Spam-Level: ** X-Spam-Status: No, score=2.984 tagged_above=-10 required=6.6 t ests=[AWL=-0.337, BAYES_50=0.001, DNS_FROM_OPENWHOIS=1.13, FH_DATE_PAST_20XX=3.188, HTML_MESSAGE=0.001, HTML_OBFUSCATE_05_10=0.001, RCVD_IN_DNSWL_LOW=-1] autolearn=no Received: from s1.mydomain.com ([127.0.0.1]) by localhost (s1.mydomain.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id RBjF7Wwr44mP for <[email protected]>; Thu, 27 Jan 2011 17:24:24 +0530 (IST) Received: from mail-qw0-f44.google.com (mail-qw0-f44.google.com [209.85.216.44]) by s1.mydomain.com (Postfix) with ESMTP id BB5DE6A6512 for <[email protected]>; Thu, 27 Jan 2011 17:24:23 +0530 (IST) Received: by qwi2 with SMTP id 2so1989393qwi.3 for <[email protected]>; Thu, 27 Jan 2011 03:54:23 -0800 (PST) MIME-Version: 1.0 Received: by 10.224.19.203 with SMTP id c11mr1587082qab.170.1296125657457; Thu, 27 Jan 2011 02:54:17 -0800 (PST) Received: by 10.220.117.17 with HTTP; Thu, 27 Jan 2011 02:54:17 -0800 (PST) Date: Thu, 27 Jan 2011 16:24:17 +0530 Message-ID: <[email protected]> Subject: test : 16:24 From: X <[email protected]> To: [email protected] Content-Type: multipart/alternative; boundary=0015175cba2865a5fe049ad1c5cd We appreciate any help that could help solve this issue :)

    Read the article

  • Is it possible to write C# code as below and send email using my home network?

    - by kedar karthik
    Is it possible to write C# code as below and send email using my home network? I have a valid user name and password on that exchange server. Is there any configuration that I can set to achieve this? BTW this code blow works when I run it within office network. I want this code to work when run from any network. String cMSExchangeWebServiceURL = (String)System.Configuration.ConfigurationSettings.AppSettings["MSExchangeWebServiceURL"]; String cEmail = (String)System.Configuration.ConfigurationSettings.AppSettings["Cemail"]; String cPassword = (String)System.Configuration.ConfigurationSettings.AppSettings["Cpassword"]; String cTo = (String)System.Configuration.ConfigurationSettings.AppSettings["CTo"]; ExchangeServiceBinding esb = new ExchangeServiceBinding(); esb.Timeout = 1800000; esb.AllowAutoRedirect = true; esb.UseDefaultCredentials = false; esb.Credentials = new NetworkCredential(cEmail, cPassword); esb.Url = cMSExchangeWebServiceURL; ServicePointManager.ServerCertificateValidationCallback += delegate(object sender1, X509Certificate certificate, X509Chain chain, SslPolicyErrors sslPolicyErrors) { return true; }; // Create a CreateItem request object CreateItemType request = new CreateItemType(); // Setup the request: // Indicate that we only want to send the message. No copy will be saved. request.MessageDisposition = MessageDispositionType.SendOnly; request.MessageDispositionSpecified = true; // Create a message object and set its properties MessageType message = new MessageType(); message.Subject = subject; message.Body = new TestOutgoingEmailServer.com.cogniti.mail1.BodyType(); message.Body.BodyType1 = BodyTypeType.HTML; message.Body.Value = body; message.ToRecipients = new EmailAddressType[3]; message.ToRecipients[0] = new EmailAddressType(); //message.ToRecipients[1] = new EmailAddressType(); //message.ToRecipients[2] = new EmailAddressType(); message.ToRecipients[0].EmailAddress = "[email protected]"; message.ToRecipients[0].RoutingType = "SMTP"; //message.CcRecipients = new EmailAddressType[1]; //message.CcRecipients[0] = new EmailAddressType(); //message.CcRecipients[0].EmailAddress = toEmailAddress.ElementAt(1).ToString(); //message.CcRecipients[0].RoutingType = "SMTP"; //There are some more properties in MessageType object //you can set all according to your requirement // Construct the array of items to send request.Items = new NonEmptyArrayOfAllItemsType(); request.Items.Items = new ItemType[1]; request.Items.Items[0] = message; // Call the CreateItem EWS method. CreateItemResponseType response = esb.CreateItem(request);

    Read the article

  • Can two Identical devices be present on the same bus in any PCI Topology

    - by vaibbhav
    As per the PCI standard, devices are identified on the basis of Vendor Id, Device Id and the bus no. All devices of same type have identical vendor id and device id. If I put two such devices on the same bus say bus 0. How will the PCI Software Subsystem distinguish between the two? If such a case is not possible in PCI, then can such thing be possible through PCI Express Switch?

    Read the article

  • Can two Identical devices be present on the same bus in any PCI Topology

    - by vaibbhav
    As per the PCI standard, devices are identified on the basis of Vendor Id, Device Id and the bus no. All devices of same type have identical vendor id and device id. If I put two such devices on the same bus say bus 0. How will the PCI Software Subsystem distinguish between the two? If such a case is not possible in PCI, then can such thing be possible through PCI Express Switch?

    Read the article

  • What info is really useful in my iptables log and how do I disable the useless bits?

    - by anthony01
    In my iptables rules files, I entered this at the end: -A INPUT -j LOG --log-level 4 --log-ip-options --log-prefix "iptables: " I DROP everything besides INPUT for SSH (port 22) I have a web server and when I try to connect to it through my browser, through a forbidden port number (on purpose), I get something like that in my iptables.log Sep 24 14:05:57 myserver kernel: [xx.xx] iptables: IN=eth0 OUT= MAC=aa:bb:cc SRC=yy.yy.yy.yy DST=xx.xx.xx.xx LEN=64 TOS=0x00 PREC=0x00 TTL=54 ID=59351 DF PROTO=TCP SPT=63776 DPT=1999 WINDOW=65535 RES=0x00 SYN URGP=0 Sep 24 14:06:01 myserver kernel: [xx.xx] iptables: IN=eth0 OUT= MAC=aa:bb:cc SRC= yy.yy.yy.yy DST=xx.xx.xx.xx LEN=48 TOS=0x00 PREC=0x00 TTL=54 ID=63377 DF PROTO=TCP SPT=63776 DPT=1999 WINDOW=65535 RES=0x00 SYN URGP=0 Sep 24 14:06:09 myserver kernel: [xx.xx] iptables: IN=eth0 OUT= MAC=aa:bb:cc SRC=yy.yy.yy.yy DST=xx.xx.xx.xx LEN=48 TOS=0x00 PREC=0x00 TTL=54 ID=55025 DF PROTO=TCP SPT=63776 DPT=1999 WINDOW=65535 RES=0x00 SYN URGP=0 Sep 24 14:06:25 myserver kernel: [xx.xx] iptables: IN=eth0 OUT= MAC=aa:bb:cc SRC=yy.yy.yy.yy DST=xx.xx.xx.xx LEN=48 TOS=0x00 PREC=0x00 TTL=54 ID=54521 DF PROTO=TCP SPT=63776 DPT=1999 WINDOW=65535 RES=0x00 SYN URGP=0 Sep 24 14:06:55 myserver kernel: [xx.xx] iptables: IN=eth0 OUT= MAC=aa:bb:cc SRC=yy.yy.yy.yy DST=xx.xx.xx.xx LEN=100 TOS=0x00 PREC=0x00 TTL=54 ID=35050 PROTO=TCP SPT=63088 DPT=22 WINDOW=33304 RES=0x00 ACK PSH URGP=0 Sep 24 14:06:55 myserver kernel: [xx.xx] iptables: IN=eth0 OUT= MAC=aa:bb:cc SRC=yy.yy.yy.yy DST=xx.xx.xx.xx LEN=52 TOS=0x00 PREC=0x00 TTL=54 ID=14076 PROTO=TCP SPT=63088 DPT=22 WINDOW=33264 RES=0x00 ACK URGP=0 Sep 24 14:06:55 myserver kernel: [xx.xx] iptables: IN=eth0 OUT= MAC=aa:bb:cc SRC=yy.yy.yy.yy DST=xx.xx.xx.xx LEN=52 TOS=0x00 PREC=0x00 TTL=54 ID=5277 PROTO=TCP SPT=63088 DPT=22 WINDOW=33248 RES=0x00 ACK URGP=0 Sep 24 14:06:56 myserver kernel: [xx.xx] iptables: IN=eth0 OUT= MAC=aa:bb:cc SRC=yy.yy.yy.yy DST=xx.xx.xx.xx LEN=100 TOS=0x00 PREC=0x00 TTL=54 ID=25501 PROTO=TCP SPT=63088 DPT=22 WINDOW=33304 RES=0x00 ACK PSH URGP=0 As you can see, I typed xx.xx.xx.xx:1999 in my browser, and it tried to connect until it timed out. 1) There are many similar lines for just one event. Do you think I need all of them? How would I avoid duplicates? 2) The last 4 lines are for my port 22. But since I allow port 22 INPUT for my web server, why are they here? 3) Do I need info like LEN,TOS,PREC and others? I'm trying to find a page that explains them one by one, by I can't find anything.

    Read the article

< Previous Page | 427 428 429 430 431 432 433 434 435 436 437 438  | Next Page >