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  • Is there a Form.Invoke() method?

    - by rubicon
    Hi, I am new to multithreading (and also to C#) so I hope this is not obvious: In my Form (WinForms application, .NET 2.0) I subscribed to an event that is raised by another object, and on handling this event I wish to change several Controls on my Form. As this event is raised in another thread than the main (UI) thread I want to marshal the call to the Form's thread. I understand I could use the Control.Invoke() method on any Control that I want to change, but as there are several of them I do not wish to do that. When searching the internet I found hints that the Form class itself provides an Invoke() method. See for example: http://marioschneider.blogspot.com/2008/04/invoke-methode-fr-multithread.html (Sorry, as I am I new user I can't seem to post more than one link. I will add more links as comments if possible.) With that, I could just wrap my event handler and then use it as if it was called on the UI thread. However, this doesn't seem to be defined in my environment, and in MSDN's System.Windows.Forms.Form documentation there's also no sign of it. Does this method exist in the .NET-Framework? I find it hard to believe that Form would not supply such a method, as it uses the same message queue the Controls on it do. (Or am I missing something here?)

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  • Scroll to item in listview in Silverlight 3.

    - by the empirical programmer
    I have a silverlight 3 app with a textbox on the main window and a childwindow that has a list of all the potential textbox values. When I open that childwindow I want it to scroll to the correct one in the list. I'm trying to do this with the code below...using the ScrollIntoView. It was not working at all until I add the UpdateLayerout(). However it does not seem to work all the time. At times it scrolls but not all the way to the item, it is a few items higher than it should be. The listbox is in an Accordion and the list items use a ItemTemplate\DataTemplate, not sure if that effects anything but thought I'd mention it. Any ideas what I'm missing in the code below? What I would like is to scroll the item to the top of the list ....any ideas how to that? (Or any other suggestions on how to code this better) Thanks! for (int index = 0; index < myList.Items.Count; index++) { object obj = myList.Items[index]; var listItem= obj as listItemObject; if (listItemObj != null) { if (string.Compare(listItemObj.id, _PastedInId, StringComparison.InvariantCultureIgnoreCase) == 0) { selectThisIndex = index; scrollToThisItem = obj; } } } myList.SelectedIndex = selectThisIndex; if (scrollToThisItem != null){ myList.UpdateLayout(); myList.ScrollIntoView(scrollToThisItem); }

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  • EF4 querying through the generations

    - by Hans Kesting
    I have a model withs Parents, Children and Grandchildren, in a many-to-many relationship. Using this article I created POCO classes that work fine, except for one thing I can't yet figure out. When I query the Parents or Children directly using LINQ, the SQL reflects the LINQ query (a .Count() executes a COUNT in the database and so on) - fine. The Parent class has a Children property, to access it's children. But (and now for the problem) this doesn't expose an IQueryable interface but an ICollection. So when I access the Children property on a particular parent all the Parent's Children are read. Even worse, when I access the Grandchildren (theParent.Children.SelectMany(child => child.GrandChildren).Count()) then for each and every child a separate request is issued to select it's grandchildren. Changing the type of the Children property from ICollection to IQueryable doesn't solve this. Apart from missing needed methods like Add() and Remove(), EF just doesn't recognize the property then. Are there correct ways (as in: low database interaction) of querying through children (and what are they)? Or is this just not possible?

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  • Dependency Injection: How to pass DB around?

    - by Stephane
    Edit: This is a conceptual question first and foremost. I can make applications work without knowing this, but I'm trying to learn the concept. I've seen lots of videos with related classes and that makes sense, but when it comes to classes wrapping around other classes, I can't seem to grasp where things should be instantiated/passed around. =-=-=-=-=-=-= Question: Let's say I have a simple page that loads data from a table, manipulates the result and displays it. Simple. I'm going to use '=' for instantiating a class and '-' for passing a class in using constructor injection. It seems to me that the database has to be passed from one end of the application to the other which doesn't seem right. Here's how I would do it if I wanted to separate concerns: index =>Controller =>Model Layer =>Database =>DAO->Database I have this rule in my head that says I'm not supposed to create objects inside other objects. So what do I do with the Database? Or even the Model for that matter? I'm obviously missing something so basic about this. I would love a simplified example so that I can move forward in my code. I feel really hamstrung by this.

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  • Generic Singleton Fasade design pattern

    - by Paul
    Hi I try write singleton fasede pattern with generics. I have one problem, how can I call method from generic variable. Something like this: T1 t1 = new T1(); //call method from t1 t1.Method(); In method SingletonFasadeMethod I have compile error: Error 1 'T1' does not contain a definition for 'Method' and no extension method 'Method' accepting a first argument of type 'T1' could be found (are you missing a using directive or an assembly reference?) Any advace? Thank, I am beginner in C#. All code is here: namespace GenericSingletonFasade { public interface IMyInterface { string Method(); } internal class ClassA : IMyInterface { public string Method() { return " Calling MethodA "; } } internal class ClassB : IMyInterface { public string Method() { return " Calling MethodB "; } } internal class ClassC : IMyInterface { public string Method() { return "Calling MethodC"; } } internal class ClassD : IMyInterface { public string Method() { return "Calling MethodD"; } } public class SingletonFasade<T1,T2,T3> where T1 : class,new() where T2 : class,new() where T3 : class,new() { private static T1 t1; private static T2 t2; private static T3 t3; private SingletonFasade() { t1 = new T1(); t2 = new T2(); t3 = new T3(); } class SingletonCreator { static SingletonCreator() { } internal static readonly SingletonFasade<T1,T2,T3> uniqueInstace = new SingletonFasade<T1,T2,T3>(); } public static SingletonFasade<T1,T2,T3> UniqueInstace { get { return SingletonCreator.uniqueInstace; } } public string SingletonFasadeMethod() { //Problem is here return t1.Method() + t2.Method() + t3.Method(); } } }

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  • Can't get horizontal scroll to work.

    - by kylex
    Here's my code in first-scene.html: <div id="main" class="palm-hasheader"> <div class="palm-header">Header</div> <div id="scrollerId" style="width:500px; height:500px" x-mojo-element="Scroller"> <div> My Text that goes on... and on... and on... horizontally... </div> </div> </div> Here my code in first-assistant.js: function FirstAssistant() { /* this is the creator function for your scene assistant object. */ } FirstAssistant.prototype.setup = function() { /* this function is for setup tasks that have to happen when the scene is created */ this.controller.setupWidget("scrollerId", this.attributes = { mode: 'horizontal' } ); }; FirstAssistant.prototype.activate = function(event) { /* put in event handlers here that should only be in effect when this scene is active. */ }; FirstAssistant.prototype.deactivate = function(event) { /* remove any event handlers you added in activate and do any other cleanup */ }; FirstAssistant.prototype.cleanup = function(event) { /* this function should do any cleanup needed before the scene is destroyed as a result of being popped off the scene stack */ }; Can't get it to scroll horizontally. What am I missing?

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  • NHibernate lazy properties behavior?

    - by GeReV
    I've been trying to get NHibernate into development for a project I'm working on at my workplace. Since I have to put a strong emphasis on performance, I've been running a proof-of-concept stress test on an existing project's table with thousands of records, all of which contain a large text column. However, when selecting a collection of these records, the select statement takes a relatively long time to execute; apparently due to the aforementioned column. The first solution that comes to mind is setting this property as lazy: <property name="Content" lazy="true"/> But there seems to be no difference in the SQL generated by NHibernate. My question is, how do lazy properties behave in NHibernate? Is there some kind of type limitations I could be missing? Should I take a different approach altogether? Using HQL's new Class(column1, column2) approach works, but lazy properties sounds like a simpler solution. It's perhaps worth mentioning I'm using NHibernate 2.1.2GA with the Castle DynamicProxy. Thanks!

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  • Picture.writeToStream() not writing out all bitmaps

    - by quickdraw mcgraw
    I'm using webview.capturePicture() to create a Picture object that contains all the drawing objects for a webpage. I can successfully render this Picture object to a bitmap using the canvas.drawPicture(picture, dst) with no problems. However when I use picture.writeToStream(fos) to serialize the picture object out to file, and then Picture.createFromStream(fis) to read the data back in and create a new picture object, the resultant bitmap when rendered as above is missing any larger images (anything over around 20KB! by observation). This occurs on all the Android OS platforms that I have tested 1.5, 1.6 and 2.1. Looking at the native code for Skia which is the underlying Android graphics library and the output file produced from the picture.writeToStream() I can see how the file format is constructed. I can see that some of the images in this Skia spool file are not being written out (the larger ones), the code that appears to be the problem is in skBitmap.cpp in the method void SkBitmap::flatten(SkFlattenableWriteBuffer& buffer) const; It writes out the bitmap fWidth, fHeight, fRowBytes, FConfig and isOpaque values but then just writes out SERIALIZE_PIXELTYPE_NONE (0). This means that the spool file does not contain any pixel information about the actual image and therefore cannot restore the picture object correctly. Effectively this renders the writeToStream and createFromStream() APIs useless as they do not reliably store and recreate the picture data. Has anybody else seen this behaviour and if so am I using the API incorrectly, can it be worked around, is there an explanation i.e. incomplete API / bug and if so are there any plans for a fix in a future release of Android? Thanks in advance.

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  • In Lua, can I easily select the Nth result without custom functions?

    - by romkyns
    Suppose I am inserting a string into a table as follows: table.insert(tbl, mystring) and that mystring is generated by replacing all occurrences of "a" with "b" in input: mystring = string.gsub(input, "a", "b") The obvious way to combine the two into one statement doesn't work, because gsub returns two results: table.insert(tbl, string.gsub(input, "a", "b")) -- error! -- (second result of gsub is passed into table.insert) which, I suppose, is the price paid for supporting multiple return values. The question is, is there a standard, built-in way to select just the first return value? When I found select I thought that was exactly what it did, but alas, it actually selects all results from N onwards, and so doesn't help in this scenario. Now I know I can define my own select as follows: function select1(n, ...) return arg[n] end table.insert(tbl, select1(1, string.gsub(input, "a", "b"))) but this doesn't look right, since I'd expect a built-in way of doing this. So, am I missing some built-in construct? If not, do Lua developers tend to use a separate variable to extract the correct argument or write their own select1 functions?

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  • mvn clean install using java 1.5 or 1.6

    - by bruce
    When I do mvn clean install, I get this error: annotations are not supported in -source 1.3 (try -source 1.5 to enable annotations) But where do I put this -source 1.5 command? I tried all permutations with mvn clean install and couldn't get it to work. So I tried putting compilation in my pom, like this: <build> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>2.0.2</version> <configuration> <source>1.6</source> <target>1.6</target> </configuration> </plugin> </plugins> But that didn't work either.. What am I missing? Thanks!

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  • jQuery - Having a problem with $(this).find(".event_recur").html()

    - by Fostah
    Hello, I am trying get the html within .event_recur. $(".entry").each(function(){ alert($(this).find(".event_recur").html()); }); <div class="entry"> <p class="event_title">June 21st Event - eat</p> <p class="event_start_date">1277160289</p> <p class="event_end_date">1277505889</p> <p class="event_body"><p>June 21-25th </p></p> <p class="event_recur"><p>No </p></p> <p class="event_body"><p>June 21-25th </p></p> <p class="event_location"><p>Pac Sun </p></p> <p class="event_categories"> Eat </p> </div> I get nothing when I do: $(".entry").each(function(){ alert($(this).find(".event_recur").html(); }); I was expecting: <p>No </p> Am I missing something? Thanks!

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  • How can I use SQL Server's full text search across multiple rows at once?

    - by Morbo
    I'm trying to improve the search functionality on my web forums. I've got a table of posts, and each post has (among other less interesting things): PostID, a unique ID for the individual post. ThreadID, an ID of the thread the post belongs to. There can be any number of posts per thread. Text, because a forum would be really boring without it. I want to write an efficient query that will search the threads in the forum for a series of words, and it should return a hit for any ThreadID for which there are posts that include all of the search words. For example, let's say that thread 9 has post 1001 with the word "cat" in it, and also post 1027 with the word "hat" in it. I want a search for cat hat to return a hit for thread 9. This seems like a straightforward requirement, but I don't know of an efficient way to do it. Using the regular FREETEXT and CONTAINS capabilities for N'cat AND hat' won't return any hits in the above example because the words exist in different posts, even though those posts are in the same thread. (As far as I can tell, when using CREATE FULLTEXT INDEX I have to give it my index on the primary key PostID, and can't tell it to index all posts with the same ThreadID together.) The solution that I currently have in place works, but sucks: maintain a separate table that contains the entire concatenated post text of every thread, and make a full text index on THAT. I'm looking for a solution that doesn't require me to keep a duplicate copy of the entire text of every thread in my forums. Any ideas? Am I missing something obvious?

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  • javascript accordion - tracking time question

    - by JohnMerlino
    Hey all, I was reading up on this javascript tutorial: http://www.switchonthecode.com/tutor...ccordion-menus Basically, it shows you how to create an accordion using pure javascript, not jquery. All made sense to me until the actual part of tracking the animation. He says "Because of all that, the first thing we do in the animation function is figure out how much time has passed since the last animation iteration." And then uses this code: Code: var elapsedTicks = curTick - lastTick; lastTick is equal to the value of when the function was called (Date().getTime()) and curTick is equal to the value when the function was received. I don't understand why we are subtracting one from the other right here. I can't imagine that there's any noticeable time difference between these two values. Or maybe I'm missing something. Is that animate() function only called once every time a menu title is clicked or is it called several times to create the incremental animation effect? setTimeout("animate(" + new Date().getTime() + "," + TimeToSlide + ",'" + openAccordion + "','" + nID + "')", 33); Thanks for any response.

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  • jquery is getting the old values from database

    - by sansknwoledge
    hi in my jsp page i am a having a jquery area which pass the values to a servlet which returns an output of dropdownlist . then the jsp file do some updation so certain values which are in the dropdownlist should not be there while repopulating. but it is not happening. my jquery code is $("#cbocode").change(function(){ var cdid=$("#cbocode option:selected"); $.get("trnDC?caseNo=20&cdid="+cdid.text(),function(data){ $("#divinstrument").html(data); }) and the servlet code is case 20:{ //jquery call String cdid=(String) request.getParameter("cdid"); Statement st = con.createStatement(); ResultSet rs = st.executeQuery("select instrumentid from mstinstrument where codeid='" + cdid + "' and rec_Status='A' and statusid='U' and Agentid='METLAB'"); if (!rs.wasNull()){ //List data=new ArrayList(); String v="<select id=cboinstr>"; while (rs.next()) { // data.add(rs.getString("vend_code")); v += "<option>" + rs.getString("instrumentid").toString() + "</option>"; } v+="</select>"; response.setContentType("text/html"); PrintWriter out = response.getWriter(); out.print(v); } else{ response.setContentType("text/html"); PrintWriter out = response.getWriter(); out.print("no data found"); } where i am missing???

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  • How to persist in order

    - by parhs
    I have two entities: EXAM and EXAM_NORMAL. EXAM @Id @GeneratedValue(strategy=GenerationType.IDENTITY) private Long id; private String name; private String codeName; @Enumerated(EnumType.STRING) private ExamType examType; @ManyToOne private Category category; @OneToMany(mappedBy="id",cascade=CascadeType.PERSIST) @OrderBy("id") private List<Exam_Normal> exam_Normal; EXAM_NORMAL @Id private Long item; @Id @ManyToOne private Exam id; @Enumerated(EnumType.STRING) private Gender gender; private Integer age_month_from; private Integer age_month_to; The problem is that if I put a list of EXAM_NORMAL at an EXAM class if I try to persist(EXAM) I get an error because it tries to persist EXAM_NORMAL first but it cant because the primary key of EXAM is missing because it isn't persisted... Is there any way to define the order? Or should I set null the list, persist and then set the list again? thanks:)

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  • undefined method `model_name' for NilClass:Class - Rails application

    - by user1270259
    So I have seen other articles here on stack about this and a lot of the time people are not doing @post = post.new. I read some where to use the plural...?? any ways I am getting this error on my discussion code: Discussion Controller class DiscussionsController < ApplicationController def index @discussion = Discussion.new @discussions = Discussion.all end def create @discussion = Discussion.create(params[:discussion]) if @discussion.save redirect_to tasks_path, :flash => {:success => 'Created a new discussion'} else redirect_to tasks_path, :flash => {:error => 'Failed to create a discussion'} end end end Discussion Form <%= form_for @discussion do |f| %> <p><%= f.label :title %> <%= f.text_field :title %></p> <p><%= f.label :content %> <%= f.text_area :content %></p> <% end %> Discussion Routes resources :discussions do resources :comments end Now as far as I know I am doing this right, because I have a task form set up essentially the same way - but I have looked at my code for hours and have googled and tried other examples and now i see this: undefined method `model_name' for NilClass:Class Extracted source (around line #1): 1: <%= form_for @discussion do |f| %> 2: 3: <p><%= f.label :title %> 4: <%= f.text_field :title %></p> Which should mean that I am missing something from my controller.....is it as asilly as a spelling mistake? .

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  • C++: Switch statement within while loop?

    - by Jason
    I just started C++ but have some prior knowledge to other languages (vb awhile back unfortunately), but have an odd predicament. I disliked using so many IF statements and wanted to use switch/cases as it seemed cleaner, and I wanted to get in the practice.. But.. Lets say I have the following scenario (theorietical code): while(1) { //Loop can be conditional or 1, I use it alot, for example in my game char something; std::cout << "Enter something\n -->"; std::cin >> something; //Switch to read "something" switch(something) { case 'a': cout << "You entered A, which is correct"; break; case 'b': cout << "..."; break; } } And that's my problem. Lets say I wanted to exit the WHILE loop, It'd require two break statements? This obviously looks wrong: case 'a': cout << "You entered A, which is correct"; break; break; So can I only do an IF statement on the 'a' to use break;? Am I missing something really simple? This would solve a lot of my problems that I have right now.

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  • Best way to store this data?

    - by Malfist
    I have just been assigned to renovate an old website, and I get to move it from some old archaic system to drupal. The only problem is that it's a real-estate system and a lot of data is stored. Currently all the information is stored in a single table, an id represents the house and then everything else is key/value pairs. There are a possible 243 keys per estate, there are 23840 estates in the system. As you can imagine the system is slow and difficult to query. I don't think a table with 243 rows would be a very good idea, and probably worse than the current situation. I've done some investigating and here's what I've found out: Missing data does not indicate a 0 value, data is merged from two, unique sources/formats. Some guessing is involved. I have no control over the source of the data. There are 4 keys that are common to all estates, all values look like something that is commonly searched for and could be indexed There are 10 keys that are in the [90-100)% range 8 of these are information like who's selling it, and it's address. The other two seem to belong with the below range There are 80 keys that are in the [80-90)% range This range seems to mostly just list room types and how many the house has (e.g. bedrooms_possible, bathrooms, family_room_3rd, etc) This range also includes some minor information like school districts, one or two more pieces of data on the address. The 179 keys that are in the [0-80)% range include all sorts of miscellaneous information about the estate My best idea was a hybrid approach, create a table that stores important, common information and keep a smaller key/value table. How would you store this information?

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  • Bind event to AJAX populated list items

    - by AnPel
    I have an unordered list with no list items. I get some information from the user, I run it through my database using AJAX and the servers sends back a JSON object response. Then I append each list item I want to display to the list using something like $('blabla').append('<li>information</li>') My question is, since the li elements were not there at the time the DOM was ready, how can I bind a click event to them? Here is my full code: $(function(){ var timer; $('#f').keyup(function(){ clearTimeout(timer); timer = setTimeout(getSuggestions, 400); }); }) function getSuggestions(){ var a = $('#f')[0].value.length; if( a < 3){ if(a == 0){ $('#ajaxerror').hide(300,function(){ $('#loading').hide(300,function(){ $('#suggest').hide(300) }) }) } return; } $('#loading').slideDown(200,function(){ $.ajax({ url: '/models/AJAX/suggest.php', dataType: 'json', data: {'data' : $('#f')[0].value }, success: function(response){ $('#ajaxerror').hide(0,function(){ $('#loading').hide(100,function(){ $('#suggest ul li').remove(); for(var b = 0; b < ( response.rows * 3); b = b + 3){ $('#suggest ul').append('<li>'+response[b]+' '+response[b+1]+' '+response[b+2]+'</li>') // MISSING SOME CODE HERE TO BIND CLICK EVENT TO NEWLY CREATED LI } $('#suggest').show(300) }) }) }, error: function(){ $('#suggest').hide(0,function(){ $('#loading').slideUp(100,function(){ $('#ajaxerror').show(300) }) }) } }) }) }

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  • Modifying Django's pre_save/post_save Data

    - by Rodrogo
    Hi, I'm having a hard time to grasp this post_save/pre_save signals from django. What happens is that my model has a field called status and when a entry to this model is added/saved, it's status must be changed accordingly with some condition. My model looks like this: class Ticket(models.Model): (...) status = models.CharField(max_length=1,choices=OFFERT_STATUS, default='O') And my signal handler, configured for pre_save: def ticket_handler(sender, **kwargs): ticket = kwargs['instance'] (...) if someOtherCondition: ticket.status = 'C' Now, what happens if I put aticket.save() just bellow this last line if statement is a huge iteration black hole, since this action calls the signal itself. And this problem happens in both pre_save and post_save. Well... I guess that the capability of altering a entry before (or even after) saving it is pretty common in django's universe. So, what I'm doing wrong here? Is the Signals the wrong approach or I'm missing something else here? Also, would it be possible to, once this pre_save/post_save function is triggered, to access another model's instance and change a specific row entry on that? Thanks

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  • Check if previous clicked value is inside an array

    - by Lelly
    I have a list with different categories. All the list item are clickable. I want the user to pick between 1 and 3 items. They can toggle their choice, but maximum is alway 3. So far, so good. Where it get tricky for me, is that I have some special categories that can't be combined with any others. When a user click on one of these, all the other categories deselect and they can't add any other, (these item have only 1 category selection possible) Exemple: Let's say "Car" is a special category. If they click on Car, everything else deselect, Car is selected, and they can't select anything else. BUT they can click again on Car to deselect it, and from there the logic start over. What's missing in my code is the part in bold just above this. My code: $j('.chooseCat li').on('click',function(){ var $this = $j(this); //list item clicked var catId = $this.children("a").attr("rel"); // list item id var specialCat = ['6','36','63']; if ($this.hasClass("selected")) { $this.removeClass("selected"); $j("#categorySuggestions p.error").hide("fast") } else { if( $j.inArray(catId, specialCat) !== -1 ) { $j('.chooseCat li').removeClass("selected"); $this.addClass("selected"); } else { if ($j('.chooseCat li.selected').length <= 2){ $this.addClass("selected"); } else { $j("#categorySuggestions p.error").show("fast").html("You cannot select any more categories"); } } } }); A working jsFiddle of where Iam at: http://jsfiddle.net/nfQum/9/

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  • jquery asp.net combo box question

    - by coson
    Good Day, I have a small form with a combo box (ASP.NET Drop Down List control) and a text box (with a DIV id txtName). When the selected index of the combo box changes, I want to clear out the text box. I understand that: $("#txtName").val(''); clears the text box value The thing is the combo box. It contains a list of integers representing the months of the year. The drop down control is called ddlMonths. $("#ddlMonths").change(function() { $("#txtName").val(''); }); I thought by using change, an onSelectedIndexChange event handler would be associated with this control. I also tried (because I've ran into the client id being mangled in ASP.NET w/ jQuery) this: $("#<%=ddlMonths.ClientID%>").change(function() { $("#<%=txtName.ClientID%>").val(''); }); and neither approach seems to be working. Am I missing something? TIA, coson

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  • Sending a message to nil?

    - by Ryan Delucchi
    As a Java developer who is reading Apple's Objective-C 2.0 documentation: I wonder as to what sending a message to nil means - let alone how it is actually useful. Taking an excerpt from the documentation: There are several patterns in Cocoa that take advantage of this fact. The value returned from a message to nil may also be valid: If the method returns an object, any pointer type, any integer scalar of size less than or equal to sizeof(void*), a float, a double, a long double, or a long long, then a message sent to nil returns 0. If the method returns a struct, as defined by the Mac OS X ABI Function Call Guide to be returned in registers, then a message sent to nil returns 0.0 for every field in the data structure. Other struct data types will not be filled with zeros. If the method returns anything other than the aforementioned value types the return value of a message sent to nil is undefined. Has Java rendered my brain incapable of grokking the explanation above? Or is there something that I am missing that would make this as clear as glass? Note: Yes, I do get the idea of messages/receivers in Objective-C, I am simply confused about a receiver that happens to be nil.

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  • What's the point of indicating AllowMultiple=false on an abstract Attribute class?

    - by tvanfosson
    On a recent question about MVC attributes, someone asked whether using HttpPost and HttpDelete attributes on an action method would result in either request type being allowed or no requests being allowed (since it can't be both a Post and a Delete at the same time). I noticed that ActionMethodSelectorAttribute, from which HttpPostAttribute and HttpDeleteAttribute both derive is decorated with [AttributeUsage(AttributeTargets.Method, AllowMultiple = false, Inherited = true)] I had expected it to not allow both HttpPost and HttpDelete on the same method because of this, but the compiler doesn't complain. My limited testing tells me that the attribute usage on the base class is simply ignored. AllowMultiple seemingly only disallows two of the same attribute from being applied to a method/class and doesn't seem to consider whether those attributes derive from the same class which is configured to not allow multiples. Moreover, the attribute usage on the base class doesn't even preclude your from changing the attribute usage on a derived class. That being the case, what's the point of even setting the values on the base attribute class? Is it just advisory or am I missing something fundamental in how they work? FYI - it turns out that using both basically precludes that method from ever being considered. The attributes are evaluated independently and one of them will always indicate that the method is not valid for the request since it can't simultaneously be both a Post and a Delete.

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  • C++ : Declaring the array size with a non-constant variable

    - by Jérôme
    I always thought that when declaring an array in C++, the size has to be a constant integer value. For instance : int MyArray[5]; // correct or const int ARRAY_SIZE = 6; int MyArray[ARRAY_SIZE]; // correct but int ArraySize = 5; int MyArray[ArraySize]; // incorrect Here is also what is explained in The C++ Programming Language, by Bjarne Stroustrup : The number of elements of the array, the array bound, must be a constant expression (§C.5). If you need variable bounds, use a vector(§3.7.1, §16.3). For example: void f(int i) { int v1[i]; // error : array size not a constant expression vector<int> v2[i]; // ok } But to my big surprise, the code above does compile fine on my system ! Here is what I tried to compile : void f(int i) { int v2[i]; } int main() { int i = 3; int v1[i]; f(5); } I got no error ! I'm using GCC v4.4.0. Is there something I'm missing ?

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