Search Results

Search found 8232 results on 330 pages for 'boolean expression'.

Page 205/330 | < Previous Page | 201 202 203 204 205 206 207 208 209 210 211 212  | Next Page >

  • Resolving HttpRequestScoped Instances outside of a HttpRequest in Autofac

    - by Page Brooks
    Suppose I have a dependency that is registered as HttpRequestScoped so there is only one instance per request. How could I resolve a dependency of the same type outside of an HttpRequest? For example: // Global.asax.cs Registration builder.Register(c => new MyDataContext(connString)).As<IDatabase>().HttpRequestScoped(); _containerProvider = new ContainerProvider(builder.Build()); // This event handler gets fired outside of a request // when a cached item is removed from the cache. public void CacheItemRemoved(string k, object v, CacheItemRemovedReason r) { // I'm trying to resolve like so, but this doesn't work... var dataContext = _containerProvider.ApplicationContainer.Resolve<IDatabase>(); // Do stuff with data context. } The above code throws a DependencyResolutionException when it executes the CacheItemRemoved handler: No scope matching the expression 'value(Autofac.Builder.RegistrationBuilder`3+<c__DisplayClass0[MyApp.Core.Data.MyDataContext,Autofac.Builder.SimpleActivatorData,Autofac.Builder.SingleRegistrationStyle]).lifetimeScopeTag.Equals(scope.Tag)' is visible from the scope in which the instance was requested.

    Read the article

  • Is this a violation of the single responsiblity principle?

    - by L. Moser
    I have the following method and interface: public object ProcessRules(List<IRule> rules) { foreach(IRule rule in rules) { if(EvaluateExpression(rule.Exp) == true) return rule.Result; } //Some error handling here for not hitting any rules } public interface IRule { Expression Exp; Object Result; int Precedence; } Because rules have a precedence, they should actually never be processed out of order. This leads me with (I think) three solutions: Sort rules before passing them into the evaluator. Change the parameter type to something that enforces a sort order. Sort within the evaluator. I like option 3 because it always ensures that it is sorted and I like option 1 because it seems more cohesive. And option 2 seems like a good compromise. Is a scenario like this context specific/subjective, or is there really a best practice to be applied here?

    Read the article

  • Octave: Multiple submatrices from a matrix

    - by fbrereto
    I have a large matrix from which I would like to gather a collection of submatrices. If my matrix is NxN and the submatrix size is MxM, I want to collect I=(N - M + 1)^2 submatrices. In other words I want one MxM submatrix for each element in the original matrix that can be in the top-left corner of such a matrix. Here's the code I have: for y = 1:I for x = 1:I index = (y - 1) * I + x; block_set(index) = big_mat(x:x+M-1, y:y+M-1) endfor endfor The output if a) wrong, and b) implying there is something in the big_mat(x:x+M-1, y:y+M-1) expression that can get me what I want without needing the two for loops. Any help would be much appreciated

    Read the article

  • Making a Label Visible/Not Visible in Delphi

    - by Hendriksen123
    I would like a button to change a label between being visible and not visible when clicked. I Tried the following code, but it doesnt work: Var: Hidden : Boolean; Begin If Hidden = True Then Begin Label6.Visible := True; Hidden := False; End; If Hidden = False Then Begin Label6.Visible := False; Hidden := True; End; It compiles, but doesn't work!

    Read the article

  • LINQ Searching Only Allowing Equivalency

    - by Mad Halfling
    Hi folks, I'm trying to filter a set of records based on a sub-object's criteria. This compiles ok recordList = recordList.Where(r => r.Areas.Where(a => a.Area == "Z").Count() > 0); but this doesn't recordList = recordList.Where(r => r.Areas.Where(a => a.Area <= "Z").Count() > 0); giving these errors Cannot convert lambda expression to type 'string' because it is not a delegate type Delegate 'System.Func' does not take '1' arguments Operator '<=' cannot be applied to operands of type 'string' and 'string' != works ok, by any sort of less than or greater than operation fails.

    Read the article

  • F# pattern matching

    - by Roger Alsing
    What would be the most effective way to express the following code? match cond.EvalBool() with | true -> match body.Eval() with | :? ControlFlowModifier as e -> match e with | Break(scope) -> e :> obj //Break is a DU element of ControlFlowModifier | _ -> next() //other members of CFM should call next() | _ -> next() | false -> null cond.EvalBool returns a boolean result where false should return null and true should either run the entire block again (its wrapped in a func called next) or if the special value of break is found, then the loop should exit and return the break value. Is there any way to compress that block of code to something smaller?

    Read the article

  • Regex Problem in PHP

    - by Chris
    I'm attempting to utilize the following Regex pattern: $regex = '/Name: [a-zA-Z ]*] [0-9]/'; When testing it in Rubular, it works fine, but when using PHP the expression never returns true, even when it should. Incidentally, if I remove the "[0-9]" part, it works fine. Is there some difference in PHP's regex syntax that I'm overlooking? Edit: I'm looking for the characters "Name:" then a name containing any number of letters or spaces, then a "]", then a space, then a single number. So "Name: Chris] 5" would return true and "Name: Chris] [lorem ipsum]" should return false. I also tried escaping the second bracket "\[" but this did not fix the problem.

    Read the article

  • How to add Focuschange Listner to listview in android

    - by jayanthgande
    Hi, I am having a listview in one of my activity.How to set foucs change listner.I tried with following block of code I am not getting result. product_search_list = (ListView) findViewById(R.id.productlist); product_search_list.setOnFocusChangeListener(onproductchangelistener); private OnFocusChangeListener onproductchangelistener = new OnFocusChangeListener() { @Override public void onFocusChange(View v, boolean hasFocus) { int index= (int) ((ListView)v).getSelectedItemId(); Log.i("index",""+index); } }; Actually on focus change of list items I want to get index of focused list item and do the necessary operations. Thanks in advance. Regards: Jayanth

    Read the article

  • How easy is it to hack a plist file in an app store app?

    - by user249488
    Don't worry, I'm not trying to hack someone else's app, if that's what you're thinking =). I want to have 2 versions of my app, a free version and a deluxe version. My plan was to use an in-app purchase to enable the deluxe version by setting a boolean value in the plist file. My question is: is this secure or is it easily circumvented? And if it is not secure, can someone suggest a simple alternative? I don't want to download additional content, I would rather keep all of the functionality within the app and enable it somehow.

    Read the article

  • How to implement a left outer join in the Entity Framework.

    - by user206736
    I have the following SQL query:- select distinct * from dbo.Profiles profiles left join ProfileSettings pSet on pSet.ProfileKey = profiles.ProfileKey left join PlatformIdentities pId on pId.ProfileKey = profiles.Profilekey I need to convert it to a LinqToEntities expression. I have tried the following:- from profiles in _dbContext.ProfileSet let leftOuter = (from pSet in _dbContext.ProfileSettingSet select new { pSet.isInternal }).FirstOrDefault() select new { profiles.ProfileKey, Internal = leftOuter.isInternal, profiles.FirstName, profiles.LastName, profiles.EmailAddress, profiles.DateCreated, profiles.LastLoggedIn, }; The above query works fine because I haven't considered the third table "PlatformIdentities". Single left outer join works with what I have done above. How do I include PlatformIdentities (the 3rd table) ? I basically want to translate the SQL query I specified at the beginning of this post (which gives me exactly what I need) in to LinqToEntities. Thanks

    Read the article

  • Trouble with Powershell and running a complex commandline

    - by Frank Rosario
    Hi, I've been trying to run the following command line from a Powershell build script we have; but keep running into issues & 'C:\Dev\Yadda\trunk\BuildScripts\U tilities\csmanage.exe' /create-deployme nt /name:yadddayaddyaddadev /label:yadddayaddyaddadev /package:https://yadddayaddyadda.blob.core.windows.net/mydeployments/20100426_202848_FamilyMoments.cspk g /config:C:\Dev\WalmartOne\trunk\yadddayaddyadda.CloudService\bin\Debug\ServiceCon figuration.cscfg /slot:Staging /hosted-service:yadddayaddyadda-dev" Note: the space in "Utilities" is intentional; trying to snif out a bug involving spaces in the executable path. I assure you, the path does exist with the space in it on my machine. What's the best way to call this command line from Powershell? I've tried Invoke-Expression, Diagnostic.Process::Start, &; each method coming up with some different type of error; usually that it could find the executable. Any constructive input is greatly appreciated. Thanks.

    Read the article

  • Android SQLite Problem: Program Crash When Try a Query!

    - by Skatephone
    Hi i have a problem programming with android SDK 1.6. I'm doing the same things of the "notepad exaple" but the programm crash when i try some query. If i try to do a query directly in to the DatabaseHelper create() metod it goes, but out of this function it doesn't. Do you have any idea? this is the source: public class DbAdapter { public static final String KEY_NAME = "name"; public static final String KEY_TOT_DAYS = "totdays"; public static final String KEY_ROWID = "_id"; private static final String TAG = "DbAdapter"; private DatabaseHelper mDbHelper; private SQLiteDatabase mDb; private static final String DATABASE_NAME = "flowratedb"; private static final String DATABASE_TABLE = "girl_data"; private static final String DATABASE_TABLE_2 = "girl_cyle"; private static final int DATABASE_VERSION = 2; /** * Database creation sql statement */ private static final String DATABASE_CREATE = "create table "+DATABASE_TABLE+" (id integer, name text not null, totdays int);"; private static final String DATABASE_CREATE_2 = "create table "+DATABASE_TABLE_2+" (ref_id integer, day long not null);"; private final Context mCtx; private static class DatabaseHelper extends SQLiteOpenHelper { DatabaseHelper(Context context) { super(context, DATABASE_NAME, null, DATABASE_VERSION); } @Override public void onCreate(SQLiteDatabase db) { db.execSQL(DATABASE_CREATE); db.execSQL(DATABASE_CREATE_2); db.delete(DATABASE_TABLE, null, null); db.delete(DATABASE_TABLE_2, null, null); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { Log.w(TAG, "Upgrading database from version " + oldVersion + " to " + newVersion + ", which will destroy all old data"); db.execSQL("DROP TABLE IF EXISTS "+DATABASE_TABLE); db.execSQL("DROP TABLE IF EXISTS "+DATABASE_TABLE_2); onCreate(db); } } public DbAdapter(Context ctx) { this.mCtx = ctx; } public DbAdapter open() throws SQLException { mDbHelper = new DatabaseHelper(mCtx); mDb = mDbHelper.getWritableDatabase(); return this; } public void close() { mDbHelper.close(); } public long createGirl(int id,String name, int totdays) { ContentValues initialValues = new ContentValues(); initialValues.put(KEY_ROWID, id); initialValues.put(KEY_NAME, name); initialValues.put(KEY_TOT_DAYS, totdays); return mDb.insert(DATABASE_TABLE, null, initialValues); } public long createGirl_fd_day(int refid, long fd) { ContentValues initialValues = new ContentValues(); initialValues.put("ref_id", refid); initialValues.put("calendar", fd); return mDb.insert(DATABASE_TABLE, null, initialValues); } public boolean updateGirl(int rowId, String name, int totdays) { ContentValues args = new ContentValues(); args.put(KEY_NAME, name); args.put(KEY_TOT_DAYS, totdays); return mDb.update(DATABASE_TABLE, args, KEY_ROWID + "=" + rowId, null) > 0; } public boolean deleteGirlsData() { if (mDb.delete(DATABASE_TABLE_2, null, null)>0) if(mDb.delete(DATABASE_TABLE, null, null)>0) return true; return false; } public Bundle fetchAllGirls() { Bundle extras = new Bundle(); Cursor cur = mDb.query(DATABASE_TABLE, new String[] {KEY_ROWID, KEY_NAME, KEY_TOT_DAYS}, null, null, null, null, null); cur.moveToFirst(); int tot = cur.getCount(); extras.putInt("tot", tot); int index; for (int i=0;i<tot;i++){ index=cur.getInt(cur.getColumnIndex("_id")); extras.putString("name"+index, cur.getString(cur.getColumnIndex("name"))); extras.putInt("totdays"+index, cur.getInt(cur.getColumnIndex("totdays"))); } cur.close(); return extras; } public Cursor fetchGirl(int rowId) throws SQLException { Cursor mCursor = mDb.query(true, DATABASE_TABLE, new String[] {KEY_ROWID, KEY_NAME, KEY_TOT_DAYS}, KEY_ROWID + "=" + rowId, null, null, null, null, null); if (mCursor != null) { mCursor.moveToFirst(); } return mCursor; } public Cursor fetchGirlCD(int rowId) throws SQLException { Cursor mCursor = mDb.query(true, DATABASE_TABLE_2, new String[] {"ref_id", "day"}, "ref_id=" + rowId, null, null, null, null, null); if (mCursor != null) { mCursor.moveToFirst(); } return mCursor; } } Tank's Valerio From Italy :)

    Read the article

  • Derived Column Editor

    - by Rob Bowman
    Hi I need to assign a formatted date to a column in a data flow. I have added a Derived Column editor and entered the following expression: "BBD" + SUBSTRING((DT_WSTR,4)DATEADD("Day",30,GETDATE()),1,4) + SUBSTRING((DT_WSTR,2)DATEADD("Day",30,GETDATE()),6,2) + SUBSTRING((DT_WSTR,2)DATEADD("Day",30,GETDATE()),9,2) The problem is that the "Derived Column Transformation Editor" automatically assigns a Data Type of "Unicode string[DT_WSTR]" and a length of "7". Howver, the length of a string is 11, therefore the following exception is thrown each time: [Best Before Date [112]] Error: The "component "Best Before Date" (112)" failed because truncation occurred, and the truncation row disposition on "output column "Comments" (132)" specifies failure on truncation. A truncation error occurred on the specified object of the specified component. Does anyone know why the edit is insisting on a length of 7? I don't seem to be able to change this. Many thanks, Rob.

    Read the article

  • can not set the bool value of app setting

    - by user262325
    Hello everyone I use the codes below to read and write a bool value from my application: -(void)SaveAppSetting; {     NSUserDefaults *defaults=[NSUserDefaults standardUserDefaults];     bool b=true;     [defaults setBool:b forKey:@"AnyKey"]; [defaults synchronize]; } -(void)LoadAppSetting; {     NSUserDefaults *defaults=[NSUserDefaults standardUserDefaults];     bool b=[defaults boolForKey: @"AnyKey"] ; } I found that "LoadAppSetting" worked well, it could get the correct value of item with key "AnyKey". The function "SaveAppSetting" looked like no function, it reported no error, but it can not change value of the item with key "AnyKey". "AnyKey" setting in Setting bundle is item Dictionary Type String PSToggleSwitchSpecifier Title String AnyKey's Title Key String AnyKey DefaultValue Boolean Checked Is there any person met the same problem? Thanks interdev

    Read the article

  • Need to debug LINQ simple queries in Visual Studio 2010

    - by maxima120
    I often get in a position when I need to know why my LINQ doesnt work as intended... I use object collections and extensions. I dont want spend more than couple of minutes on it. LINQ supposed to make developer's life easier not harder. I hoped VS 2010 will have it fixed but I now use RC and it still doesnt let me type LINQ and check what is going on... Says as before "Expression cannot contain lambda expressions"... Is there some add-on for Visual Studio so I can quickly and effectively run ad-hoc queries and find out what is going on and where I am wrong?

    Read the article

  • C# Finisar SQLite DateTime Comparison Problem

    - by Emanuel
    My "task" database table look like this: [title] [content] [start_date] [end_date] [...] [...] [01.06.2010 20:10:36] [06.06.2010 20:10:36] [...] [...] [05.06.2010 20:10:36] [06.06.2010 20:10:36] And I want to find only those records that meet the condition that a given day is between start_date and end_date. I've tried the following SQL expression: SELECT * FROM task WHERE strftime ('%d', start_date) <= @day AND @day <= strftime ('%d', end_date) Where @day is an SQLiteParameter (eq 5). But no result is returned. How can I solve this problem? Thanks.

    Read the article

  • Odd compiler error on if-clause without braces

    - by DisgruntledGoat
    The following Java code is throwing a compiler error: if ( checkGameTitle(currGame) ) ArrayList<String> items = parseColumns( tRows.get(rowOffset+1), currGame, time, method ); checkGameTitle is a public static function, returning a boolean. The errors are all of the type "cannot find symbol" with the symbols being variable ArrayList, variable String and variable items. However, if I add {curly braces} then the code compiles with no errors. Why might this be? Is there some ambiguity on the if clause without them?

    Read the article

  • How to get a continuous Touch Event?

    - by daliz
    My class extends View and I need to get continuous touch events on it. If I use: public boolean onTouchEvent(MotionEvent me) { if(me.getAction()==MotionEvent.ACTION_DOWN) { myAction(); } return true; } ... the touch event is captured once. What if I need to get continuous touches without moving the finger? Please, tell me I don't need to use threads or timers. My app is already too much heavy. Thanks.

    Read the article

  • Linq to sql translation to sql of custom method

    - by DJPB
    hi there is there a way to translate an expression to sql to use with linq to sql? for example I have a method that compares two values example: MyComparer.Compare(value1, value2, ">") return value1 > value2 MyComparer.Compare(value1, value2, "=") return value1 == value2 MyComparer.Compare(value1, value2, "<=") return value1 <= value2 and i would like a query like var list = from i in dataContext.items where MyComparer.Compare(i.value, someValue, "some operator") select ... this won't work because, obviously, MyComparer doesn't translate to sql maybe this is a twisted question, but how can i translate this method to sql or is this possible? tks

    Read the article

  • How can I use a Shader in XNA to color single pixels?

    - by George Johnston
    I have a standard 800x600 window in my XNA project. My goal is to color each individual pixel based on a rectangle array which holds boolean values. Currently I am using a 1x1 Texture and drawing each sprite in my array. I am very new to XNA and come from a GDI background, so I am doing what I would have done in GDI, but it doesn't scale very well. I have been told in another question to use a Shader, but after much research, I still haven't been able to find out how to accomplish this goal. My application loops through the X and Y coordinates of my rectangular array, does calculations based on each value, and reassigns/moves the array around. At the end, I need to update my "Canvas" with the new values. A smaller sample of my array would look like: 0,0,0,0,0,0,0 0,0,0,0,0,0,0 0,0,0,0,0,0,0 1,1,1,1,1,1,1 1,1,1,1,1,1,1 How can I use a shader to color each pixel?

    Read the article

  • Why isn't my bundle getting passed?

    - by NickTFried
    I'm trying to pass a bundle of two values from a started class to my landnav app, but according to the debug nothing is getting passed, does anyone have any ideas why? package edu.elon.cs.mobile; import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.EditText; public class PointEntry extends Activity{ private Button calc; private EditText longi; private EditText lati; private double longid; private double latd; public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.pointentry); calc = (Button) findViewById(R.id.coorCalcButton); calc.setOnClickListener(landNavButtonListener); longi = (EditText) findViewById(R.id.longitudeedit); lati = (EditText) findViewById(R.id.latitudeedit); } private void startLandNav() { Intent intent = new Intent(this, LandNav.class); startActivityForResult(intent, 0); } private OnClickListener landNavButtonListener = new OnClickListener() { @Override public void onClick(View arg0) { Bundle bundle = new Bundle(); bundle.putDouble("longKey", longid); bundle.putDouble("latKey", latd); longid = Double.parseDouble(longi.getText().toString()); latd = Double.parseDouble(lati.getText().toString()); startLandNav(); } }; } This is the class that is suppose to take the second point package edu.elon.cs.mobile; import com.google.android.maps.GeoPoint; import com.google.android.maps.MapActivity; import com.google.android.maps.MapController; import com.google.android.maps.MapView; import com.google.android.maps.MyLocationOverlay; import com.google.android.maps.Overlay; import android.content.Context; import android.graphics.drawable.Drawable; import android.hardware.Sensor; import android.hardware.SensorEvent; import android.hardware.SensorEventListener; import android.hardware.SensorManager; import android.location.Location; import android.location.LocationManager; import android.os.Bundle; import android.util.Log; import android.widget.EditText; import android.widget.TextView; public class LandNav extends MapActivity{ private MapView map; private MapController mc; private GeoPoint myPos; private SensorManager sensorMgr; private TextView azimuthView; private double longitudeFinal; private double latitudeFinal; double startTime; double newTime; double elapseTime; private MyLocationOverlay me; private Drawable marker; private GeoPoint finalPos; private SitesOverlay myOverlays; public LandNav(){ startTime = System.currentTimeMillis(); } public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.landnav); Bundle bundle = this.getIntent().getExtras(); if(bundle != null){ longitudeFinal = bundle.getDouble("longKey"); latitudeFinal = bundle.getDouble("latKey"); } azimuthView = (TextView) findViewById(R.id.azimuthView); map = (MapView) findViewById(R.id.map); mc = map.getController(); sensorMgr = (SensorManager) getSystemService(Context.SENSOR_SERVICE); LocationManager lm = (LocationManager)getSystemService(Context.LOCATION_SERVICE); Location location = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER); int longitude = (int)(location.getLongitude() * 1E6); int latitude = (int)(location.getLatitude() * 1E6); finalPos = new GeoPoint((int)(latitudeFinal*1E6), (int)(longitudeFinal*1E6)); myPos = new GeoPoint(latitude, longitude); map.setSatellite(true); map.setBuiltInZoomControls(true); mc.setZoom(16); mc.setCenter(myPos); marker = getResources().getDrawable(R.drawable.greenmarker); marker.setBounds(0,0, marker.getIntrinsicWidth(), marker.getIntrinsicHeight()); me = new MyLocationOverlay(this, map); myOverlays = new SitesOverlay(marker, myPos, finalPos); map.getOverlays().add(myOverlays); } @Override protected boolean isRouteDisplayed() { return false; } @Override protected void onResume() { super.onResume(); sensorMgr.registerListener(sensorListener, sensorMgr.getDefaultSensor(Sensor.TYPE_ORIENTATION), SensorManager.SENSOR_DELAY_UI); me.enableCompass(); me.enableMyLocation(); //me.onLocationChanged(location) } protected void onPause(){ super.onPause(); me.disableCompass(); me.disableMyLocation(); } @Override protected void onStop() { super.onStop(); sensorMgr.unregisterListener(sensorListener); } private SensorEventListener sensorListener = new SensorEventListener() { @Override public void onAccuracyChanged(Sensor arg0, int arg1) { // TODO Auto-generated method stub } private boolean reset = true; @Override public void onSensorChanged(SensorEvent event) { newTime = System.currentTimeMillis(); elapseTime = newTime - startTime; if (event.sensor.getType() == Sensor.TYPE_ORIENTATION && elapseTime > 400) { azimuthView.setText(Integer.toString((int) event.values[0])); startTime = newTime; } } }; }

    Read the article

  • Create New Pseudo Variables in Squeak

    - by Artium
    Large part of squeak is implemented using squeak itself. I am curious to know if pseudo variables such as self or true are also implemented using squeak. If the answer is yes, where the implementation located? Specifically, assume that I want to add new subclass of "Boolean" called "Other" which will represent a third option: neither true nor false. I want that other, the only instance of Other to be similar to the true/false global singletons. Any ideas? Thank you.

    Read the article

  • ASP.NET Binding integer to CheckBox's Checked field

    - by Sung Meister
    I have a following ListView item template, in which I am trying to bind integer value to Checked property of CheckBox. IsUploaded value contains only 0 and 1... <asp:ListView ID="trustListView" runat="server"> <ItemTemplate> <asp:CheckBox ID="isUploadedCheckBox" runat="server" Checked='<%# Bind("IsUploaded") %>' /> </ItemTemplate> </asp:ListView> But ASP.NET complains that Exception Details: System.InvalidCastException: Sepcified cast is not valid Even though following code using DataBinder.Eval() works, I need to have a 2-way binding, thus need to use Bind(). <asp:CheckBox ID="isUploadedCheckBox2" runat="server" Checked='<%# Convert.ToBoolean( DataBinder.Eval(Container.DataItem, "IsUploaded"))) %>' /> How can I convert 0's and 1's to boolean using Bind()? [ANSWER] I have extended auto-generated type through partial class by adding a new property mentioned in the answer by Justin

    Read the article

  • Rails uniqueness constraint and matching db unique index for null column

    - by Dave
    I have the following in my migration file def self.up create_table :payment_agreements do |t| t.boolean :automatic, :default => true, :null => false t.string :payment_trigger_on_order t.references :supplier t.references :seller t.references :product t.timestamps end end I want to ensure that if a product_id is specified it is unique but I also want to allow null so I have the following in my model: validates :product_id, :uniqueness => true, :allow_nil => true Works great but I should then add an index to the migration file add_index :payment_agreements, :product_id, :unique => true Obviously this will throw an exception when two null values are inserted for product_id. I could just simply omit the index in the migration but then there's the chance that I'll get two PaymentAgreements with the same product_id as shown here: Concurrency and integrity My question is what is the best/most common way to deal with this problem

    Read the article

  • Where and which data to save into session on an ASP.NET MVC 2 application?

    - by Shaharyar
    I am having some trouble saving the state of my current view. Currenly I have several selectlist calling their own Action method on the controller that returns the Index view with the filtered model based on the values of the selectlist. I have also written a little FileResult action that creates a csv file based on the current model. But I am only covering one selectlist right now as I only save the value of selectList1 into the session and access it with Session["SelectListValue1"] What are the best practices in this situation? Should I redo the entire (each action for each SelectList) part? Should I save each SelectLists value into the session and check if it's null? Or should I just save the Lambda Expression into the session and modify it during every call?

    Read the article

< Previous Page | 201 202 203 204 205 206 207 208 209 210 211 212  | Next Page >