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  • what patern is layerd architechture in asp.net ?

    - by haansi
    Hi, I am a asp.net developer and don't know much about patterns and architecture. I will very thankful if you can please guide me here. In my web applications I use 4 layers. Web site project (having web forms + code behind cs files, user controls + code behind cs files, master pages + code behind cs files) CustomTypesLayer a class library (having custom types, enumerations, DTOs, constructers, get, set and validations) BusinessLogicLayer a class library (having all business logic, rules and all calls to DAL functions) DataAccessLayer a class library( having just classes communicating to database.) -My user interface just calls BusinessLogicLayer. BusinessLogicLayer do proecessign in it self and for data it calls DataAccessLayer funtions. -Web forms do not calls directly DAL. -CustomTypesLayer is shared by all layers. Please guide me is this approach a pattern ? I though it may be MVC or MVP but pages have there code behind files as well which are confusing me. If it is no patren is it near to some patren ? pleaes guide thanks

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  • returning a pointed to an object within a std::vector

    - by memC
    I have a very basic question on returning a reference to an element of a vector . There is a vector vec that stores instances of class Foo. I want to access an element from this vector . ( don't want to use the vector index) . How should I code the method getFoo here? #include<vector> #include<stdio.h> #include<iostream> #include<math.h> using namespace std; class Foo { public: Foo(){}; ~Foo(){}; }; class B { public: vector<Foo> vec; Foo* getFoo(); B(){}; ~B(){}; }; Foo* B::getFoo(){ int i; vec.push_back(Foo()); i = vec.size() - 1; // how to return a pointer to vec[i] ?? return vec.at(i); }; int main(){ B b; b = B(); int i = 0; for (i = 0; i < 5; i ++){ b.getFoo(); } return 0; }

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  • auto div height

    - by Geln
    <html><head><title>Test</title> <style> .main{width:600px;border:1px solid red; } .main .left{background:lightblue; width:100px;clear:both; float:left;} .main .right{margin-left:100px;background:lightyellow; } </style> </head><body> <div class="main"> <div class="left"> title </div> <div class="right"> <div id="item">item</div> <div id="item">item</div> <div id="item">item</div> <div id="item">item</div> <div id="item">item</div> <div id="item">item</div> <div id="item">item</div> </div> </div> </body></html> How to change the CSS to make the page display like the dialog shows? PS,I think it's a way that to make the "left" div's height auto expend when the height of the "right" div or parent div expend, but I don't know how.

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  • Doesn't (didn't) Scala have automatically generated setters?

    - by Malvolio
    Google and my failing memory are both giving me hints that it does, but every attempt is coming up dry. class Y { var y = 0 } var m = new Y() m.y_(3) error: value y_ is not a member of Y Please tell me I am doing something wrong. (Also: please tell me what it is I am doing wrong.) EDIT The thing I am not doing wrong, or at least not the only thing I am doing wrong, is the way I am invoking the setter. The following things also fail, all with the same error message: m.y_ // should be a function valued expression m.y_ = (3) // suggested by Google and by Mchl f(m.y_) // where f takes Int => Unit as an argument f(m.y) // complains that I am passing in Int not a function I am doing this all through SimplyScala, because I'm too lazy and impatient to set up Scala on my tiny home machine. Hope it isn't that... And the winner is ... Fabian, who pointed out that I can't have a space between the _ and the =. I thought out why this should be and then it occurred to me: The name of the setter for y is not y_, it is y_= ! Observe: class Y { var y = 0 } var m = new Y() m.y_=(3) m.y res1: Int = 3 m.y_= error: missing arguments for method y_= in class Y; follow this method with `_` if you want to treat it as a partially applied function m.y_= ^ m.y_=_ res2: (Int) => Unit = def four(f : Int => Unit) = f(4) four(m.y_=) m.y res3: Int = 4 Another successful day on StackExchange.

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  • How can I prevent infinite recursion when using events to bind UI elements to fields?

    - by Billy ONeal
    The following seems to be a relatively common pattern (to me, not to the community at large) to bind a string variable to the contents of a TextBox. class MyBackEndClass { public event EventHandler DataChanged; string _Data; public string Data { get { return _Data; } set { _Data = value; //Fire the DataChanged event } } } class SomeForm : // Form stuff { MyBackEndClass mbe; TextBox someTextBox; SomeForm() { someTextBox.TextChanged += HandleTextBox(); mbe.DataChanged += HandleData(); } void HandleTextBox(Object sender, EventArgs e) { mbe.Data = ((TextBox)sender).Text; } void HandleData(Object sender, EventArgs e) { someTextBox.Text = ((MyBackEndClass) sender).Data; } } The problem is that changing the TextBox fires the changes the data value in the backend, which causes the textbox to change, etc. That runs forever. Is there a better design pattern (other than resorting to a nasty boolean flag) that handles this case correctly? EDIT: To be clear, in the real design the backend class is used to synchronize changes between multiple forms. Therefore I can't just use the SomeTextBox.Text property directly. Billy3

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  • Why Is the sender type null when dealing with events

    - by ChloeRadshaw
    From C# Via CLR: Note A lot of people wonder why the event pattern requires the sender parameter to always be of type Object After all, since the MailManager will be the only type raising an event with a NewMail EventArgs object, it makes more sense for the callback method to be prototyped like this: void MethodName(Mai l Manager sender, NewMail EventArgs e); The pattern requires the sender parameter to be of type Object mostly because of inheritance What if Mai lManager were used as a base class for SmtpMailManager? In this case, the callback method should have the sender parameter prototyped as SmtpMailManager instead of Mail Manager, but this can’t happen because SmtpMai lManager just inherited the NewMai l event So the code that was expecting SmtpMail Manager to raise the event must still have to cast the sender argument to SmtpMailManager In other words, the cast is still required, so the sender parameter might as well be typed as Obj ect The next reason for typing the sender parameter as Obj ect is just fexibility It allows the delegate to be used by multiple types that offer an event that passes a NewMail EventArgs object For example, a PopMai lManager class could use the delegate even if this class were not derived from Mail Manager I just simply cannot understand why the sender is an object - Why can it not be generified? so most of the time we do not need to do generic casts

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  • Is method reference caching a good idea in Java 8?

    - by gexicide
    Consider I have code like the following: class Foo { Y func(X x) {...} void doSomethingWithAFunc(Function<X,Y> f){...} void hotFunction(){ doSomethingWithAFunc(this::func); } } Consider that hotFunction is called very often. Would it then be advisable to cache this::func, maybe like this: class Foo { Function<X,Y> f = this::func; ... void hotFunction(){ doSomethingWithAFunc(f); } } As far as my understanding of java method references goes, the Virtual Machine creates an object of an anonymous class when a method reference is used. Thus, caching the reference would create that object only once while the first approach creates it on each function call. Is this correct? Should method references that appear at hot positions in the code be cached or is the VM able to optimize this and make the caching superfluous? Is there a general best practice about this or is this highly VM-implemenation specific whether such caching is of any use?

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  • CodeModel help needed for right-hand singleton.getinstance() assignment.

    - by antarti
    I've been able to generate 99% of what I need with the CodeModel API, but I am stumped here... Using the various "directXX" methods does not add import statements to the generated code, and I can work without the "directXXX" type of methods except for one place in a generated class. Suppose I desire a generated method like: /** * Copies data from this Value-Obj instance, to the returned PERSON instance. * * @return PERSON * */ public PERSON mapVOToPERSON() throws MappingException { Mapper mapper = (com.blah.util.MapperSingleton.getMapperInstance()); return mapper.map(this, PERSON.class); } You can see the right hand of the Mapper assignment in parens. Emitting the entire package+class was the only way I could find to just declare "SomeSingleton.someMethod()" on the right hand side and have the generated code compile. Without the MapperSingleton being added to the object model, there is no import generated... Questions: 1) Is there a way to force an import to be generated? 2) How to declare an expression that gives me the right side of the Mapper assignment within the object model (so that an import of MapperSingleton gets generated. Any help appreciated...

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  • Passing user_id, site_id, and question_id to same table on create...

    - by bgadoci
    I can't seem to figure out how to do this. I am trying to pass four different variables to a single table. To be more specific I am trying to create a "like" in a likes table that also captures the site_id (like an answer), user_id, and the question_id. Here is the set up. class Like < ActiveRecord::Base belongs_to :site belongs_to :user belongs_to :question end I will spare you the reverse, has_many associations but they are there. Here is the likes controller where I think the problem is. class LikesController < ApplicationController def create @user = current_user @site = Site.find(params[:site_id]) @like = @site.likes.create!(params[:like]) @like.user = current_user @like.save respond_to do |format| format.html { redirect_to @site} format.js end end end This code successfully passes the like and site_id but after many different variations of trying I can't get it to pass the question id. Here is my form: /views/sites/_site.html.erb (though the partial is being displayed in the /views/questions/show.html.erb file). <% remote_form_for [site, Like.new] do |f| %> <%= f.hidden_field :site_name, :value => "#{site.name}" %> <%= f.hidden_field :ip_address, :value => "#{request.remote_ip}" %> <%= f.hidden_field :like, :value => "1" %> <%= submit_tag "^" , :class => 'voteup' %> <% end %>

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  • issue with tab bar view displaying a compound view

    - by ambertch
    I created a tab bar application, and I make the first tab a table. So I create a tableView controller, and go about setting the class identity of the view controller for the first tab to my tableView controller. This works fine, and I see the contents of the table filling up the whole screen. However, this is not what I actually want in the end goal - I would like a compound window having multiple views: - the aforementioned table - a custom view with data in it So what I do is create a nib for this content (call it contentNib), change the tab's class from the tableView controller to a generic UIViewController, and set the nib of that tab to this new contentNib. In this new contentNib I drag on a tableView and set File's Owner to the TableViewController. I then link the dataSource and delegate to file's owner (which is TableViewController). Surprisingly this does not work and I receive the error: **Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[UIViewController tableView:numberOfRowsInSection:]: unrecognized selector sent to instance 0x3b0f910'** This is bewildering to me since the file's owner is the TableViewController, which has been assigned to be both the dataSource and delegate. Does someone have either insight into my confusions, or a link to an example of how to have a compound view include a tableView? *update* I see this in the Apple TableView programming guide: "Note: You should use a UIViewController subclass rather than a subclass of UITableViewController to manage a table view if the view to be managed is composed of multiple subviews, one of which is a table view. The default behavior of the UITableViewController class is to make the table view fill the screen between the navigation bar and the tab bar (if either are present)." <----- I don't really get what this is telling me to do though... if someone can explain or point me to an example I'd be much appreciated!

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  • Align child element to bottom with CSS

    - by alex
    I have a form input, and the label spans multiple lines, and I want the corresponding checkbox to appear at the bottom (last line of the label element). Here is what I was playing with CSS .standard-form { width: 500px; border: 1px solid red; } .standard-form .input-row { overflow: hidden; margin-bottom: 0.8em; } .standard-form label { width: 25%; float: left; } .standard-form .input-container { width: 70%; float: right; } .standard-form .checkbox .input-container { display: table-cell; height: 100%; vertical-align: text-bottom; } HTML <form class="standard-form"> <div class="input-row checkbox" id="permission"> <label for="input-permission"> Do I hereby grant you permission to do whatever tasks are neccessary to achieve an ideal outcome? </label> <div class="input-container"> <input type="checkbox" id="input-permission" name="permission" value="true" /> </div> </div> </form> It is also online at JSbin. Is there any way to do this? I notice that div.input-container isn't expanding, which is the old multi column problem with CSS. I thought I could get this going with display: table-cell and vertical-align: bottom but I haven't been able to do it yet. I don't mind that IE6/7 won't render it correctly.

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  • How can I avoid encoding mixups of strings in a C/C++ API?

    - by Frerich Raabe
    I'm working on implementing different APIs in C and C++ and wondered what techniques are available for avoiding that clients get the encoding wrong when receiving strings from the framework or passing them back. For instance, imagine a simple plugin API in C++ which customers can implement to influence translations. It might feature a function like this: const char *getTranslatedWord( const char *englishWord ); Now, let's say that I'd like to enforce that all strings are passed as UTF-8. Of course I'd document this requirement, but I'd like the compiler to enforce the right encoding, maybe by using dedicated types. For instance, something like this: class Word { public: static Word fromUtf8( const char *data ) { return Word( data ); } const char *toUtf8() { return m_data; } private: Word( const char *data ) : m_data( data ) { } const char *m_data; }; I could now use this specialized type in the API: Word getTranslatedWord( const Word &englishWord ); Unfortunately, it's easy to make this very inefficient. The Word class lacks proper copy constructors, assignment operators etc.. and I'd like to avoid unnecessary copying of data as much as possible. Also, I see the danger that Word gets extended with more and more utility functions (like length or fromLatin1 or substr etc.) and I'd rather not write Yet Another String Class. I just want a little container which avoids accidental encoding mixups. I wonder whether anybody else has some experience with this and can share some useful techniques. EDIT: In my particular case, the API is used on Windows and Linux using MSVC 6 - MSVC 10 on Windows and gcc 3 & 4 on Linux.

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  • HIbernate 3.5.1 - can I just drop in EHCache 2.0.1?

    - by caerphilly
    I'm using Hibernate 3.5.1, which comes with EHCache 1.5 bundled. If I want to use the latest EHCache release (2.0.1), is it just a matter of removing the ehcache-1.5.jar from my project, and replacing with ehcache-core-2.0.1.jar? Any issues to be aware of? Also - is a cache "region" in the Hibernate mapping file that same as a cache "name" in the ehcache configuration xml? What I want to do is define 2 named cache regions - one for read-only reference entities that won't change (lookup lists etc), and one for all other entities. So in ehcache I want to define two elements; <cache name="readonly"> ... </cache> <cache name="mutable"> ... </cache> And then in my Hibernate mapping files, I will specify the cache to be used for each entity: <hibernate-mapping> <class name="lookuplist"> <cache region="readonly" usage="read-only"/> <property> ... </property> </class> </hibernate-mapping> Will that work? Some of the documentation seems to imply that a separate region/cache gets created for each mapped class... Thanks.

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  • Setting up a view to draw to in Objective-C (iPhone) ?

    - by Johannes Jensen
    Okay, so, I'm all new to iPhone and stuff, but I'm not even at programming, I have many years of experience with ActionScript 2.0 and 3.0, I want to set up a view, that I can also pass variables to. The view is gonna draw everything with Quartz. I tried to make another game where I tried to add a pointer to a NSMutableArray to the view class, but it didn't work cause I didn't know how to store an actual class. I wanted to do like: [myView setNeedsDisplay]; but I had to do [(View*)self.view setNeedsDisplay]; didn't really work out in the end... Okay, so now I got: - (void) viewDidLoad { [super viewDidLoad]; viewClass = [[View class] retain]; gameView = [[[viewClass alloc] initWithFrame: CGRectZero] retain]; [gameView setNeedsDisplay]; } This is in my drawInContext:context, which is fired by drawRect: Also, my drawRect does [self drawInContext: UIGraphicsGetCurrentContext()]; CGContextSetStrokeColorWithColor(context, [[UIColor blackColor] CGColor]); CGContextSetLineWidth(context, 3.0); CGContextSetLineCap(context, kCGLineCapRound); CGContextSetLineJoin(context, kCGLineJoinRound); CGMutablePathRef aPath = CGPathCreateMutable(); CGPathMoveToPoint(aPath, nil, 5, 5); CGPathAddLineToPoint(aPath, nil, 45, 43); CGContextAddPath(context, aPath); CGContextStrokePath(context); Nothing happens. Help? Oh yeah, I get this error: : invalid context for each time I use those functions. :[ Thanks!

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  • Android getSelectedItem, how to use?

    - by user1881184
    Im trying use the spinner control result in order to point it to another screen that would be on the app. For example in the spinner control if the user chose chevy it would then take you to another screen which is coded in chevy.xml and Chevy.class. This is what i have thus far and need some help, as our book only used getSelectedItem and the example was only for an output statement. Please help. import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.widget.AdapterView; import android.widget.AdapterView.OnItemSelectedListener; import android.widget.Spinner; public class Mainpage extends Activity implements OnItemSelectedListener { String carChoice, chevy, ford, dodge, toyota; public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); /* carChoice = group.getSelectedItem().toString(); } if (carChoice.compareTo(chevy)==0) { startActivity(new Intent(Mainpage.this, Chevy.class)); */ } public void onItemSelected(AdapterView<?> arg0, View arg1, int arg2, long arg3) { final Spinner group = (Spinner) findViewById(R.id.carGroup); group.setOnItemSelectedListener(this); // TODO Auto-generated method stub String selected = group.getItemAtPosition(1).toString(); } public void onNothingSelected(AdapterView<?> arg0) { // TODO Auto-generated method stub } }

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  • Getting all the classes in project and their packages from CodeRush extension

    - by drasto
    I've spent some time trying to find a way CodeRush could add using when it finds undeclared element that is in the fact class name with no using added. The solution suggested in this answer to my question (Refactor_resolve) does not work (bugged?). In a process I found out that writing plug-ins for CodeRush is easy, so I decided to code this functionality myself (and share it). I'd only implement a CodeProvider (like in this tutorial). The only thinks I need to do the job are answers to this questions: At the start up of my plugin I need to get a list (set, map, whatever) of all classes and their packages. This means all the classes(interfaces...) and their packages in project, and within all referenced libraries. And I also need to receive updated on this (when user adds reference, creates new class). Can I get this from some CodeRush classes or maybe VS interface available from CodeProvider class? How do I add created CodeProvider to the pop-up that is shown when user hovers over an Issue?

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  • Adding cancel ability and exception handling to async code.

    - by Rob
    I have this sample code for async operations (copied from the interwebs) public class LongRunningTask { public LongRunningTask() { //do nowt } public int FetchInt() { Thread.Sleep(2000); return 5; } } public delegate TOutput SomeMethod<TOutput>(); public class GoodPerformance { public void BeginFetchInt() { LongRunningTask lr = new LongRunningTask(); SomeMethod<int> method = new SomeMethod<int>(lr.FetchInt); // method is state object used to transfer result //of long running operation method.BeginInvoke(EndFetchInt, method); } public void EndFetchInt(IAsyncResult result) { SomeMethod<int> method = result.AsyncState as SomeMethod<int>; Value = method.EndInvoke(result); } public int Value { get; set; } } Other async approaches I tried required the aysnc page attribute, they also seemed to cancel if other page elements where actioned on (a button clicked), this approach just seemed to work. I’d like to add a cancel ability and exception handling for the longRunningTask class, but don’t erm, really know how.

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  • Hovering a div shows hidden div - jquery to prototype conversion

    - by phil
    I may get killed for this but I have been trying for a few days using Prototype to show a hidden div when hovering over another div. I have this working fine in jquery but I could use some help porting it over to prototype. The code sample: <script type="text/javascript"> $(document).ready(function(){ $(".recent-question").hover(function(){ $(this).find(".interact").fadeIn(2.0); }, function(){ $(this).find(".interact").fadeOut(2.0); }); }); </script> <div class="recent-question"> <img src="images/new/img-sample.gif" alt="" width="70" height="60" /> <div class="question-text"> <h3>Heading</h3> <p><a href="#">Yadda Yadda Yadda</p> </div> <div class="interact" style="display:none;"> <ul> <li><a href="#">Choice1</a></li> <li><a href="#">Choice2</a></li> <li><a href="#">Choice3</a></li> </ul> </div> </div> So basically when I hover over a recent-question div i would like the div.interact to fade in or appear at all. The above code is for jquery but I am required to use prototype for this project. Any help converting would be greatly appreciated. Thanks!

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  • Active State Image Display

    - by fmz
    I have some images that need to change, based not only on hover, but also on active state. If you look at the page here: http://site427.mysite4now.net/tazthedog/site1/ There are some tabs with Screen Printing Quick Links, etc. The tab image is associated with the link and displays properly. The icon in tabs defaults to the gray and turns blue on mouse over, however, I also need it to be blue on the "active" state. Here is the css: .quick-links em:hover { background: transparent url(../images/quick-links.png) 10px 9px no-repeat ; display: block ; float: left; } Here is the html: <ul class="tabs"> <li class="quick-links"> <a href="#quickLinks" id=""> <em> <span>Screen Printing Quick Links</span> </em> </a> </li> <li class="distributor-ql"> <a href="#distributorQL" id=""> <em> <span>Dealer &amp; Distributor Quick Links</span> </em> </a> </li> </ul> I tried adding a .quick-links em:active... but that doesn't maintain it. I know there is a way to keep the icon blue while in the active state, I just need a little help to understand what that is. Thanks!

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  • Is it possible to create ostream object, which outputs to multiple destinations?

    - by fiktor
    In 0-th approximation I have a class class MyClass{ public: ... std::ostream & getOStream(){return f;} private: ofstream f; ... }; Which is used sometimes in the following way: MyClass myclass; myclass.getOStream()<<some<<information<<printed<<here; But now I want to change the class MyClass, so that information will be printed both to f and to std::out, i.e. I want the above line to be equivalent to myclass.f<<some<<information<<printed<<here; std::cout<<some<<information<<printed<<here; I don't know any good way to do that. Do you? Is there any standard solution (for example in stl or in boost)? P.S. I tried to search on this, but it seems that I don't know good keywords. Words multiple, output, ostream, C++, boost seem to be too general.

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  • Importing a div's content from a Static HTML file using PHP or jQuery or Ajax?

    - by Vikram
    Hello friends a newbie question... The Issue is like this: I have a static HTML file and I want to import just a portion of that file into another page. How can I do that. Example Code: <!DOCTYPE html> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Some title here</title> <link rel="stylesheet" type="text/css" href="styles.css" /> </head> <body> <div id="box-1"> <div class="block"> <!-- Some code here --> </div> </div> <div id="box-2"> <div class="block"> <!-- Some code here --> </div> </div> <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script> <script src="script.js"></script> </body> </html> Now what I want is to read this HTML file and import just this bit: <div id="box-1"> <div class="block"> <!-- Some code here --> </div> </div> Is there a way of doing it? Kindly help. Even a PHP, jQuery, Ajax or any other solution will also do. Please help me.

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  • Positioning a Comment Input Field

    - by John
    Hello, What is a good way to give the input field below the three characteristics listed? Characteristics: -Always 30 px from the left side of the browser window. -Always 30 px below the words "Add a comment" if no comments have been added. -Always 30 px below the preceding comment if one or more comment has been added. Thanks in advance, John HTML / PHP Code: <div class="addacomment"><label for="title">Add a comment:</label></div> <div class="commentbox"><input class="commentsubfield" name="title" type="title" id="title" maxlength="1000"></div> CSS (thusfar I have no declarations for the "commentbox" selector): .commentsubfield { width: 390px; height: 90px; border: 1px solid #999999; padding: 5px; } .addacomment { position:absolute; width:250px; left:30px; top:180px; text-align: left; margin-bottom:3px; padding:0px; font-family:Arial, Helvetica, sans-serif; font-size: 12px; color:#000000; }

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  • Margin for select option in IE and chrome is not working

    - by Sardor
    I am setting a css class to some select options in JS. This class includes margin style. It is working in the FF but not in IE and chrome. window.onload = function() { replace('edit-field-region-tid'); replace('edit-tid'); } function replace(id) { var i = 0; var s = document.getElementById(id); for (i; i < s.options.length; i++) { if (find(s.options[i].text, id, i)) { s.options[i].setAttribute("class", "sub_options"); } } } function find(str, id, option_id) { var i; var s = document.getElementById(id); for (i = 0; i < str.length; i++) { if (str.charAt(i) == '-') { s.options[option_id].text = str.cutAt(0, ""); return true; } } return false; } String.prototype.cutAt = function(index, char) { return this.substr(index+1, this.length); } And CSS: .sub_options{ margin-left:20px; text-indent:-2px; } Any ideas thanks!

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  • How to write curiously recurring templates with more than 2 layers of inheritance?

    - by Kyle
    All the material I've read on Curiously Recurring Template Pattern seems to one layer of inheritance, ie Base and Derived : Base<Derived>. What if I want to take it one step further? #include <iostream> using std::cout; template<typename LowestDerivedClass> class A { public: LowestDerivedClass& get() { return *static_cast<LowestDerivedClass*>(this); } void print() { cout << "A\n"; } }; template<typename LowestDerivedClass> class B : public A<LowestDerivedClass> { public: void print() { cout << "B\n"; } }; class C : public B<C> { public: void print() { cout << "C\n"; } }; int main() { C c; c.get().print(); // B b; // Intentionally bad syntax, // b.get().print(); // to demonstrate what I'm trying to accomplish return 0; } How can I rewrite this code to compile without errors (and output "C\nB\n")?

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  • VB.NET CInt(Long) behaving differently in 32- and 64-bit environments

    - by LocoDelAssembly
    Hello everybody, this is my first message here. Today I had a problem converting a Long (Int64) to an Integer (Int32). The problem is that my code was always working in 32-bit environments, but when I try THE SAME executable in a 64-bit computer it crashes with a System.OverflowException exception. I've prepared this test code in VS2008 in a new project with default settings: Module Module1 Sub Main() Dim alpha As Long = -1 Dim delta As Integer Try delta = CInt(alpha And UInteger.MaxValue) Console.WriteLine("CINT OK") delta = Convert.ToInt32(alpha And UInteger.MaxValue) Console.WriteLine("Convert.ToInt32 OK") Catch ex As Exception Console.WriteLine(ex.GetType().ToString()) Finally Console.ReadLine() End Try End Sub End Module On my 32-bit setups (Windows XP SP3 32-bit and Windows 7 32-bit) it prints "CINT OK", but in the 64-bit computer (Windows 7 64-bit) that I've tested THE SAME executable it prints the exception name only. Is this behavior documented? I tried to find a reference but failed miserably. For reference I leave the MSIL code too: .method public static void Main() cil managed { .entrypoint .custom instance void [mscorlib]System.STAThreadAttribute::.ctor() = ( 01 00 00 00 ) // Code size 88 (0x58) .maxstack 2 .locals init ([0] int64 alpha, [1] int32 delta, [2] class [mscorlib]System.Exception ex) IL_0000: nop IL_0001: ldc.i4.m1 IL_0002: conv.i8 IL_0003: stloc.0 IL_0004: nop .try { .try { IL_0005: ldloc.0 IL_0006: ldc.i4.m1 IL_0007: conv.u8 IL_0008: and IL_0009: conv.ovf.i4 IL_000a: stloc.1 IL_000b: ldstr "CINT OK" IL_0010: call void [mscorlib]System.Console::WriteLine(string) IL_0015: nop IL_0016: ldloc.0 IL_0017: ldc.i4.m1 IL_0018: conv.u8 IL_0019: and IL_001a: call int32 [mscorlib]System.Convert::ToInt32(int64) IL_001f: stloc.1 IL_0020: ldstr "Convert.ToInt32 OK" IL_0025: call void [mscorlib]System.Console::WriteLine(string) IL_002a: nop IL_002b: leave.s IL_0055 } // end .try catch [mscorlib]System.Exception { IL_002d: dup IL_002e: call void [Microsoft.VisualBasic]Microsoft.VisualBasic.CompilerServices.ProjectData::SetProjectError(class [mscorlib]System.Exception) IL_0033: stloc.2 IL_0034: nop IL_0035: ldloc.2 IL_0036: callvirt instance class [mscorlib]System.Type [mscorlib]System.Exception::GetType() IL_003b: callvirt instance string [mscorlib]System.Type::ToString() IL_0040: call void [mscorlib]System.Console::WriteLine(string) IL_0045: nop IL_0046: call void [Microsoft.VisualBasic]Microsoft.VisualBasic.CompilerServices.ProjectData::ClearProjectError() IL_004b: leave.s IL_0055 } // end handler } // end .try finally { IL_004d: nop IL_004e: call string [mscorlib]System.Console::ReadLine() IL_0053: pop IL_0054: endfinally } // end handler IL_0055: nop IL_0056: nop IL_0057: ret } // end of method Module1::Main I suspect that the instruction that is behaving differently is either conv.ovf.i4 or the ldc.i4.m1/conv.u8 pair. If you know what is going on here please let me know Thanks

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