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  • How To Select First Ancestor That Matches A Selector?

    - by Zach
    General: How can I select the first matching ancestor of an element in jQuery? Example: Take this HTML block <table> <tbody> <tr> <td> <a href="#" class="remove">Remove</a> </td> </tr> <tr> <td> <a href="#" class="remove">Remove</a> </td> </tr> </tbody> </table> I can remove a row in the table by clicking "Remove" using this jQuery code: $('.remove').click(function(){ $(this).parent().parent().hide(); return false; }); This works, but it's pretty fragile. If someone puts the <a> into a <div>, for example, it would break. Is there a selector syntax in jQuery that follows this logic: "Here's an element, now find the closest ancestor that matches some selection criteria and return it" Thanks

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  • Is there a way in VS2008 (c#) to see all the possible exception types that can originate from a meth

    - by Matt
    Is there a way in VS2008 IDE for c# to see all the possible exception types that can possibly originate from a method call or even for an entire try-catch block? I know that intellisense or the object browser tells me this method can throw these types of exceptions but is there another way than using the object browser everytime? Something more accessible when coding? Furthermore, I don't think intellisense or the object browser do anything more than read the XML code comments. Shouldn't it be possible to scan a class's source and find all the exception types that can be thrown. (Forget path-ing based on method input, just scan the code for exception types) Am I wrong? Extending this idea, you should be able to hover over the 'try' or 'catch' keywords and present a tooltip with all the types of exceptions that can be thrown. My question boils down to, does a VS2008 add on like this exist? Does VS2010 do this perhaps? If not, could you implement it the way I've described, by scanning the class code for thrown exception types and would people find it useful. Exceptions bubble up so you have to scan every bit of code every method call, which I guess could be impractical, though I suppose you could build an index the first time and increase your speed that way. (It might be a cool little project....)

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  • Error In VB.Net code

    - by Michael
    I am getting the error "Format Exception was unhandled at "Do While objectReader.Peek < -1 " and after. any help would be wonderful. 'Date: Class 03/20/2010 'Program Purpose: When code is executed data will be pulled from a text file 'that contains the named storms to find the average number of storms during the time 'period chosen by the user and to find the most active year. between the range of 'years 1990 and 2008 Option Strict On Public Class frmHurricane Private _intNumberOfHuricanes As Integer = 5 Public Shared _intSizeOfArray As Integer = 7 Public Shared _strHuricaneList(_intSizeOfArray) As String Private _strID(_intSizeOfArray) As String Private _decYears(_intSizeOfArray) As Decimal Private _decFinal(_intSizeOfArray) As Decimal Private _intNumber(_intSizeOfArray) As Integer Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load 'The frmHurricane load event reads the Hurricane text file and 'fill the combotBox object with the data. 'Initialize an instance of the StreamReader Object and declare variable page 675 on the book Dim objectReader As IO.StreamReader Dim strLocationAndNameOfFile As String = "C:\huricanes.txt" Dim intCount As Integer = 0 Dim intFill As Integer Dim strFileError As String = "The file is not available. Please restart application when available" 'This is where we code the file if it exist. If IO.File.Exists(strLocationAndNameOfFile) Then objectReader = IO.File.OpenText(strLocationAndNameOfFile) 'Read the file line by line until the file is complete Do While objectReader.Peek <> -1 **_strHuricaneList(intCount) = objectReader.ReadLine() _strID(intCount) = objectReader.ReadLine() _decYears(intCount) = Convert.ToDecimal(objectReader.ReadLine()) _intNumber(intCount) = Convert.ToInt32(objectReader.ReadLine()) intCount += 1** Loop objectReader.Close() 'With any luck the data will go to the Data Box For intFill = 0 To (_strID.Length - 1) Me.cboByYear.Items.Add(_strID(intFill)) Next Else MsgBox(strFileError, , "Error") Me.Close() End If End Sub

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  • how the get estimated output in timer

    - by ratty
    i have working with twp timer,the code below using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; namespace example { public partial class Form1 : Form { int i = 0; int j = 0; public Form1() { InitializeComponent(); timer1.Interval = 3000; } private void button1_Click(object sender, EventArgs e) { timer1.Enabled = true; } private void timer1_Tick(object sender, EventArgs e) { i++; timer2.Enabled = true; if (i < 3) time1(i); else timer1.Enabled = false; } private void timer2_Tick(object sender, EventArgs e) { j++; timer2.Interval = timer1.Interval / 5; if (j < 5) time2(j); else timer2.Enabled = false; } private void time1(int i) { MessageBox.Show(i.ToString(), "First Timer"); } private void time2(int j) { MessageBox.Show(j.ToString(), "SecondTimer"); } } } when running this program it gives output like this firsttimer:1 secondTimer:1 secondTimer:2 secondTimer:3 secondTimer:4 firsttimer:2 in message box but when debugging debug cannot move that order.after finisheg the secondtimer:2 it gose back to first timer. but i need to go for how i am output get i need for this in another application. why it occurs

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  • Selecting an option with given value

    - by Maven
    I am trying to select a particular option from a select list depending on the value, I have following markup: <select name="class" id="class"> <option value="1">679460ED-0B15-4ED9-B3C8-A8C276DF1C82</option> <option value="2">B99BF873-7DF0-4E7F-95FF-3F1FD1A26139</option> <option value="3">1DCD5AD7-F57C-414</option> <option value="4">6B0170AA-F044-4F9C-8BB8-31A51E452CE4</option> <option value="5">C6A8B</option> <option value="6">1BBD6FA4-335A-4D8F-8681-DFED317B8052</option> <option value="7">727D71AB-F7D1-4B83-9D6D-6BEEAAB</option> <option value="8">BC4DE8A2-C864-4C7C-B83C-EE2450AF11B1</option> <option value="9">AIR CONDITIONING SYSTEM</option> <option value="10">POWER GENERATION SYSTEM</option> </select> <script> selectThisValue('#class',3); </script> in .js function selectThisValue(element,value) { console.log(value); var elem = $(element + ' option[value=' + value + ']'); console.log(elem); elem.attr("selected", "selected"); } Results for console.log are as follows: 3 [prevObject: i.fn.i.init[1], context: document, selector: "#class option[value=3]", jquery: "1.10.2", constructor: function…] But this is not working, no errors are given but nothing happens also. Please help identifying the where am I wrong.

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  • Overriding CSS style 'display:none' in javascript

    - by jsarma
    I'm trying to add a checkbox toggle that hides and shows list elements by changing their style display attribute from "none" to "inline", but it's not working. I'm setting the attribute's style to "display:none" in the CSS file. Then I set it to "display:inline" in javascript when someone checks a box. The javascript is successfully changing the element's property to inline, but for some reason the element remains invisible. If I do the opposite, by setting the display to inline in the CSS and overriding it to none in the javascript, it works fine. I don't see why this would work one way but not the other. I'm using chrome. Here is the code. Any feedback is appreciated. CSS file: #tabmenu li[status='disabled'] a, a.active, #disabled { color: #777777; background: #DDDDDD; font: normal 1em Arial; border: 1px solid black; border-radius: inherit; padding: 0px 5px 0px 5px; margin: 0px; text-decoration: none; cursor:hand; display:none; } HTML: <ul id="tabmenu"> <li name='tab' id='tab1' selected='no' status='disabled'></li> </ul> JAVASCRIPT (from command line, or onchange of a checkbox) tab = document.getElementById('tab1'); tab.style.display = 'inline';

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  • Good C++ array class for dealing with large arrays of data in a fast and memory efficient way?

    - by Shane MacLaughlin
    Following on from a previous question relating to heap usage restrictions, I'm looking for a good standard C++ class for dealing with big arrays of data in a way that is both memory efficient and speed efficient. I had been allocating the array using a single malloc/HealAlloc but after multiple trys using various calls, keep falling foul of heap fragmentation. So the conclusion I've come to, other than porting to 64 bit, is to use a mechanism that allows me to have a large array spanning multiple smaller memory fragments. I don't want an alloc per element as that is very memory inefficient, so the plan is to write a class that overrides the [] operator and select an appropriate element based on the index. Is there already a decent class out there to do this, or am I better off rolling my own? From my understanding, and some googling, a 32 bit Windows process should theoretically be able address up to 2GB. Now assuming I've 2GB installed, and various other processes and services are hogging about 400MB, how much usable memory do you think my program can reasonably expect to get from the heap? I'm currently using various flavours of Visual C++.

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  • jquery displaying table rows dynamically in dom belonging to one/more particular class

    - by whatf
    I have the basic html structure: <table> <tbody> <tr class="1"> <td> <p style="font-size:large"> <span class="muted"> This is the first object </span> </p> </td> </tr> <tr class="2"> <td> <p style="font-size:large"> <span class="muted"> This is second object </span> </p> </td> </tr> <tr class="3"> <p style="font-size:large"> <span class="muted"> this is the third object </span> </p> </td> </tr> </tbody> </table> and then I have check boxes, the functionality i want is, if checkbox 1 is checked, only the tr with class 1 be displayed. if checkbox 2 and 3 are clicked, the tr with class 1 gets hidden and 2, 3 show in the dom. again if checkbox 2,*3* are unchecked and 1 is checked tr with class 2, 3 do not show and 1 is showed. How can this be done in jQuery?

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  • Audit many-to-many relationship in NHibernate

    - by Kendrick
    I have implemented listeners to audit changes to tables in my application using IPreUpdateEventListener and IPreInsertEventListener and everything works except for my many-to-many relationships that don't have additional data in the joining table (i.e. I don't have a POCO for the joining table). Each auditable object implements an IAuditable interface, so the event listener checks to see if a POCO is of type IAuditable, and if it is it records any changes to the object. Look up tables implement an IAuditableProperty inteface, so if a property of the IAuditable POCO is pointing to a lookup table, the changes are recorded in the log for the main POCO. So, the question is, how should I determine I'm working with a many-to-many collection and record the changes in my audit table? //first two checks for LastUpdated and LastUpdatedBy ommitted for brevity else if (newState[i] is IAuditable) { //Do nothing, these will record themselves separately } else if (!(newState[i] is IAuditableProperty) && (newState[i] is IList<object> || newState[i] is ISet)) { //Do nothing, this is a collection and individual items will update themselves if they are auditable //I believe this is where my many-to-many values are being lost } else if (!isUpdateEvent || !Equals(oldState[i], newState[i]))//Record only modified fields when updating { changes.Append(preDatabaseEvent.Persister.PropertyNames[i]) .Append(": "); if (newState[i] is IAuditableProperty) { //Record changes to values in lookup tables if (isUpdateEvent) { changes.Append(((IAuditableProperty)oldState[i]).AuditPropertyValue) .Append(" => "); } changes.Append(((IAuditableProperty)newState[i]).AuditPropertyValue); } else { //Record changes for primitive values if(isUpdateEvent) { changes.Append(oldState[i]) .Append(" => "); } changes.Append(newState[i]); } changes.AppendLine(); }

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  • Python "callable" attribute (pseudo-property)

    - by mgilson
    In python, I can alter the state of an instance by directly assigning to attributes, or by making method calls which alter the state of the attributes: foo.thing = 'baz' or: foo.thing('baz') Is there a nice way to create a class which would accept both of the above forms which scales to large numbers of attributes that behave this way? (Shortly, I'll show an example of an implementation that I don't particularly like.) If you're thinking that this is a stupid API, let me know, but perhaps a more concrete example is in order. Say I have a Document class. Document could have an attribute title. However, title may want to have some state as well (font,fontsize,justification,...), but the average user might be happy enough just setting the title to a string and being done with it ... One way to accomplish this would be to: class Title(object): def __init__(self,text,font='times',size=12): self.text = text self.font = font self.size = size def __call__(self,*text,**kwargs): if(text): self.text = text[0] for k,v in kwargs.items(): setattr(self,k,v) def __str__(self): return '<title font={font}, size={size}>{text}</title>'.format(text=self.text,size=self.size,font=self.font) class Document(object): _special_attr = set(['title']) def __setattr__(self,k,v): if k in self._special_attr and hasattr(self,k): getattr(self,k)(v) else: object.__setattr__(self,k,v) def __init__(self,text="",title=""): self.title = Title(title) self.text = text def __str__(self): return str(self.title)+'<body>'+self.text+'</body>' Now I can use this as follows: doc = Document() doc.title = "Hello World" print (str(doc)) doc.title("Goodbye World",font="Helvetica") print (str(doc)) This implementation seems a little messy though (with __special_attr). Maybe that's because this is a messed up API. I'm not sure. Is there a better way to do this? Or did I leave the beaten path a little too far on this one? I realize I could use @property for this as well, but that wouldn't scale well at all if I had more than just one attribute which is to behave this way -- I'd need to write a getter and setter for each, yuck.

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  • DynamicContent.html: Write a JavaScript in an HTML document that can change the content of an HTML e

    - by A sw A
    ShowHide.html: Write a JavaScript in an HTML document that displays an image and allows the user to toggle the image between appearing and not appearing in the document. Place your image in a (division) tag that has a style attribute. “style.visibility” can take two values: “visible” and “hidden”. The document has a button called “Toggle Image”, which calls the toggle function upon the event “onclick”. DynamicColors.html: Write a JavaScript in an HTML document that changes the background and foreground colors of the body of a document according to the user input. The document has two input texts: background color and foreground color. The colors change when the event “onchange” occurs as you type in the text input and the event handler is called. Your event handler takes two parameters: “where”, and “newColor”. To change the document color and background color you need to change the elements document.body.style.color and document.body.style.backgroundColor. Available colors are: black, silver, gray, white, maroon, red, purple, fuchsia, green, lime, olive, yellow, navy, blue, teal, and aqua. DynamicContent.html: Write a JavaScript in an HTML document that can change the content of an HTML element (a help box). The content of an element is accessed through its “value” property. The content of a help box can change depending on the placement of the mouse cursor. When the cursor is placed over a particular input field (“onmouseover” event), the help box can display advice on how the field is to be filled. When the cursor is moved away from the input field (“onmouseout” event), the help box content changes to simply indicate that assistance is available. Your messages are stored in an array of strings.

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  • Something wrong on my very first LINQ to SQL c # code

    - by user334813
    using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; namespace Advanced_LinQ_Query { public partial class Form1 : Form { public Form1() { InitializeComponent(); } private DataClasses1DataContext database = new DataClasses1DataContext(); private void Form1_Load(object sender, EventArgs e) { database.Log= Console.Out; comboBox.SelectedIndex=0; } private void titleBindingNavigatorSaveItem_Click(object sender, EventArgs e) { Validate(); titleBindingSource.EndEdit(); database.SubmitChanges(); comboBox.SelectedIndex=0; } private void comboBox_SelectedIndexChanged(object sender, EventArgs e) { switch (comboBox.SelectedIndex) { case 0: titleBindingSource.DataSource = from Title in database.Titles orderby Title.BookTitle select Title; break; case 1: titleBindingSource.DataSource = from Title in database.Titles where Title.Copyright == "2008" orderby Title.BookTitle select Title; break; case 2: titleBindingSource.DataSource = from Title in database.Titles where Title.BookTitle.EndsWith("How to Program") orderby Title.BookTitle select Title; break; } titleBindingSource.MoveFirst(); } } } no connection seems to built after debugging between Title table in my database (book.mdf) and titleBindingSource! Where is the problem?

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  • Why would gnu ld link order causes Signal 11 (SEGV) on startup?

    - by Benoit
    We are building a large application in C++ that includes the use of many (static) libraries. We have a problem where the application crashes on startup with a Signal 11, before we even reach main. After much debugging, we have observed that if we explicitly reference an object file so its link order is early, the program crashes on startup. If the file is referenced later (or not referenced at all), the program does not crash. To be clear, there is NO code invoked directly from this object file. However, as it is C++, there might be static objects that do get constructed (it's a CORBA IDL generated file). We use the -Wl,--start-group ... --end-group arguments to multi-pass link the symbols since the libraries are interdependent. Here is a representation of what I mean. This is what the linker's object file order is: Order 1 Order 2 Order 3 foo.o foo.o foo.o ... ... ... main.o main.o main.o crasher.o libA.o libA.o libA.o LibB.o LibB.o LibB.o LibC.o LibC.o LibC.o crasher.o Results: NO CRASH NO CRASH CRASH Does any one have an idea why the linkage order has an effect on the crash? It would be nice if we could force the crasher.o to link later, but we're really after an explanation. Also, is there a way to force the linker to place crasher.o towards the end? Just to add to the fun, in actuality, crasher.o is part of a Library in the --start/--end-group.

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  • SLRequest return nil before block complete

    - by jaytr0n
    I'm having a little trouble thinking through this and deciding if it's a design flaw on my behalf or if I'm missing a piece that could make this work. Basically I'm using the new SLRequest to make a Twitter API call. After the data is returned, I'd like to put it into an object and return that object: -(AUDSlide *) getFollowerSlide { SLRequest *getRequest = [SLRequest requestForServiceType:SLServiceTypeTwitter requestMethod:SLRequestMethodGET URL:[NSURL URLWithString:[NSString stringWithFormat:@"https://api.twitter.com/1.1/followers/ids.json?user_id=%@", [[self.twitterAccount valueForKey:@"properties"] valueForKey:@"user_id"]]] parameters:nil]; getRequest.account = twitterAccount; AUDSlide *slide = [[AUDSlide alloc] init]; [getRequest performRequestWithHandler:^(NSData *responseData, NSHTTPURLResponse *urlResponse, NSError *error) { if ([urlResponse statusCode] == 200) { NSError *jsonError = nil; NSDictionary *list = [NSJSONSerialization JSONObjectWithData:responseData options:0 error:&jsonError]; NSLog(@"Number of Followers: %u", [[list objectForKey:@"ids"] count]); slide.title = @"Followers"; slide.number = [NSString stringWithFormat:@"%u",[[list objectForKey:@"ids"] count]]; } else{ slide.title = @"Error"; slide.number = [NSString stringWithFormat: @"E%u", [urlResponse statusCode]]; } }]; return slide; } Of course the slide is returned before the call is complete and returns a nil object. So I'm not sure if I should try to force this into a synchronous request (that seems like it could be a bad idea) or rethink the design. Does anyone have any advice?

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  • PHP: cannot matching string "<br />

    - by Patrick
    hi, I'm having problems with string matching in PHP. I've 2 html elements in my page, I've copy pasted here the content with Firebug <div class="field-item odd"> <div class="field-label-inline-first"> Year:</div> 2009 </div> <div class="field-item odd"> <div class="field-label-inline-first"> Synopsis:</div> &lt;br /&gt; </div> This php line works perfectly (the element with 2009 is detected) <?php if ($items[0]['view'] == '2009') : echo "ok"; ?> However I'm not able to match the string containing element: <?php if ($items[0]['view'] == '<br />') : echo "ok"; ?> //doesn't work <?php if ($items[0]['view'] == '&lt;br /&gt;') : echo "ok"; ?> //again doesn't work any tip ? To give you some context: The strings are produced by CKEditor, an editor I'm using in my Drupal back-end. When I leave empty this editor, the tag is displayed on the string as plain text (because I set "plain text" as formatting option in the back-end) Thanks

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  • ref and out parameters in C# and cannot be marked as variant.

    - by Water Cooler v2
    What does the statement mean? From here ref and out parameters in C# and cannot be marked as variant. 1) Does it mean that the following can not be done. public class SomeClass<R, A>: IVariant<R, A> { public virtual R DoSomething( ref A args ) { return null; } } 2) Or does it mean I cannot have the following. public delegate R Reader<out R, in A>(A arg, string s); public static void AssignReadFromPeonMethodToDelegate(ref Reader<object, Peon> pReader) { pReader = ReadFromPeon; } static object ReadFromPeon(Peon p, string propertyName) { return p.GetType().GetField(propertyName).GetValue(p); } static Reader<object, Peon> pReader; static void Main(string[] args) { AssignReadFromPeonMethodToDelegate(ref pReader); bCanReadWrite = (bool)pReader(peon, "CanReadWrite"); Console.WriteLine("Press any key to quit..."); Console.ReadKey(); } I tried (2) and it worked.

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  • An Array returned by a model association is not an Array?

    - by Warren
    We have a model association that looks something like this: class Example < ActiveRecord::Base has_many :others, :order => 'others.rank' end The rank column is an integer type. The details of these particular models are not really important though as we have found the same problem with other has_many associations between other models. We have also added to the Enumerable module: module Enumerable def method_missing(name) super unless name.to_s[0..7] == 'collect_' method = name.to_s[8..-1] collect{|element| element.send(method)} end end This adds a collect_id method that we can use to get an array of record ids from an array of ActiveRecord objects. So if we use a normal ActiveRecord find :all, we get a nice array which we can then use collect_id on but if we use Example.others.collect_id, we get NoMethodError: undefined method `collect_id' for #<Class:0x2aaaac0060a0> Example.others.class returns "Array" so is it lying or confused? Our solution thus far has been to use it this way: Example.others.to_a.collect_id This works but this seems a bit strange. Why would you have to do that? We are on Ruby 1.8.7 and Rails 2.3.4

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  • jquery problem with toggle event only fireing on the 2nd click...

    - by Ronedog
    Can anyone explain why the following jquery only fires the 2nd toggle event and how to fix it? Specifically, every time I click the nested < a element it brings up the alert "2nd click". I tested the selector to make sure it was selecting the element properly and it does, or at least it inserted a class without any problems. The selector is selecting the very last node in the unordered list that has an anchor tag. $("#nav li:not(:has(li)) a").toggle(function() { //1st click alert("1st Click"); }, function() { //2nd click alert("2nd Click"); }); Nested HTML structure that fails: <ul id="nav"> <li> <span>stuff</span> <a href="#">Cat 1</a> <ul> <li> <span>stuff</span> <a href="#">Subcat1</a> <ul> <li> <span>Stuff</span> <a href="#">Subcat Details</a> </li> </ul> </li> </ul> </li> </ul> However, this works right and fires both click events: <ul id="nav"> <li> <span>stuff</span> <a href="#">Cat 1</a> </li> </ul>

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  • Casting error in my form

    - by Siva
    I have a ComboBox in a DataGridView. However I get an error when I run it: Unable to cast object of type 'System.Windows.Forms.DataGridView' to type 'System.Windows.Forms.ComboBox'. What can I do to resolve this error? ComboBox comboBox; private void dataGridView1_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e) { if (e.Control is ComboBox) { comboBox = e.Control as ComboBox; if (dataGridView1.CurrentCell.ColumnIndex >= 0) { System.Diagnostics.Debug.WriteLine("Edit Control Showing"); comboBox.SelectedIndexChanged -= new EventHandler(comboBoxItems_SelectedIndexChanged); comboBox.SelectedIndexChanged += new EventHandler(comboBoxItems_SelectedIndexChanged); } } } void comboBoxItems_SelectedIndexChanged(object sender, EventArgs e) { try { int comboBoxSelectedIndex = ((ComboBox)sender).SelectedIndex; string comboboxSelectedValue = ((ComboBox)sender).SelectedText; int gridViewSelectedRow = dataGridView1.CurrentRow.Index; if (comboBoxSelectedIndex >= 0 && gridViewSelectedRow >= 0) { System.Diagnostics.Debug.WriteLine("ComboBox Index - " + comboBoxSelectedIndex); System.Diagnostics.Debug.WriteLine("GridView Index - " + gridViewSelectedRow); if (comboBox != null) { comboBox.SelectedIndexChanged -= new EventHandler(comboBoxItems_SelectedIndexChanged); } } } catch(Exception E) { } }

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  • Calling member functions dynamically

    - by user652511
    I'm pretty sure it's possible to call a class and its member function dynamically in Delphi, but I can't quite seem to make it work. What am I missing? // Here's a list of classes (some code removed for clarity) moClassList : TList; moClassList.Add( TClassA ); moClassList.Add( TClassB ); // Here is where I want to call an object's member function if the // object's class is in the list: for i := 0 to moClassList.Count - 1 do if oObject is TClass(moClassList[i]) then with oObject as TClass(moClassList[i]) do Foo(); I get an undeclared identifier for Foo() at compile. Clarification/Additional Information: What I'm trying to accomplish is to create a Change Notification system between business classes. Class A registers to be notified of changes in Class B, and the system stores a mapping of Class A - Class B. Then, when a Class B object changes, the system will call a A.Foo() to process the change. I'd like the notification system to not require any hard-coded classes if possible. There will always be a Foo() for any class that registers for notification. Maybe this can't be done or there's a completely different and better approach to my problem. By the way, this is not exactly an "Observer" design pattern because it's not dealing with objects in memory. Managing changes between related persistent data seems like a standard problem to be solved, but I've not found very much discussion about it. Again, any assistance would be greatly appreciated. Jeff

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  • VB.NET: WithEvents not Working

    - by Hei
    Hello All, I have the following classes: Public Class Email Private Shared ReadOnly EMAIL_REGEX = "\b[a-zA-Z]+[a-zA-Z0-9._+-]+@" + _ "[a-zA-Z0-9.-]+\.[a-zA-Z]{2,3}\b" Private _email As String Public Event emailCreated() ' Declare empty constructor private so the only way to create an object ' is using new (email) Private Sub New() End Sub Sub New(ByVal email As String) If Regex.IsMatch(email, EMAIL_REGEX) Then _email = email RaiseEvent emailCreated() Else Throw New Exception("Email Not Valid") End If End Sub ReadOnly Property Email() As String Get Return _email End Get End Property End Class And Public Class EmailForm WithEvents myEmail As Email Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Try myEmail = New Email(TextBox1.Text) Catch ex As Exception MessageBox.Show("Exception: " & ex.Message) End Try End Sub Public Sub emailCreated() Handles myEmail.emailCreated MessageBox.Show("New Email Created") End Sub End Class If a create a wrong email lets say "email" the exception is correctly cached and a message is showed however is i input a valid email the event is not raised, the object is being created but no message is shown and no error or exception is thrown i suspect it has something to do with using "myemail = new Email(email)" but i have seen examples of using new with withevents with no problem. I would apreciate any input about this problem thank you

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  • Mystery: How does Google do cross-domain iframe communication?

    - by Shraga
    Hi everyone, When you host Googles web search element on a page, a div is created which incorporates an iframe which points to a Google adsense ads page. However, if there are no ads for the specific query, Google somehow changes the class on YOUR domain to render the div (and iframe) invisible. They are NOT using postMessage, as it also works in IE7. They are also not using the fragment identifier method, as no hash appears in the url. So how do they do it? To check what I'm saying just put the following into a regular html page: <!-- Google Custom Search Element --> <div id="cse" style="width:100%;">Loading</div> <script src="http://www.google.com/jsapi" type="text/javascript"></script> <script type="text/javascript"> google.load('search', '1'); google.setOnLoadCallback(function(){ new google.search.CustomSearchControl().draw('cse'); }, true); </script> and then do a search for "cars" (or anything else that will definitely have ads) and then for "wzxv", which has no ads...

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  • How can I filter using the current value of a text box in a jQuery selector?

    - by spudly
    I have a validation script that checks for data-* attributes to determine which fields are required. If an element has the 'data-required-if' attribute (which has a jQuery selector as it's value), it checks to see if any elements are found that match that selector. If any are found, the field is required. It does something similar to the following: $('[data-required-if]').each(function () { var selector = $(this).attr('data-required-if'), required = false; if ( !$(selector).length ) { required = true; // do something if this element is empty } }); This works great, but there's a problem. When you use the attribute selector to filter based on the current value of a text field, it really filters on the initial value of the text field. <input type='text' id='myinput' value='initial text' /> <input type='text' id='dependent_input' value='' data-required-if="#myinput[value='']" /> // Step 1: type "foobar" in #myinput // Step 2: run these lines of code: <script> $('#myinput').val() //=> returns "foobar" $('#myinput[value="foobar"]').length //=> returns 0 </script> I understand why it's doing that. jQuery probably uses getAttribute() in the background. Is there any other way to filter based on the current value of an input box using purely jQuery selectors?

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  • self-destructing objects in php5?

    - by user151841
    I am working on a class in php that is basically an interface to a database row. I wanted to create a delete() method that would 1. delete the database row and 2. destroy the instance of itself so that further attempts to manipulate the row via the object would throw warnings. Doing some googling, it seems that, in php5, it's not possible for an object to unset itself. http://bugs.php.net/bug.php?id=36971 In fact they discuss the very situation I was wanting to do :( So how should I proceed? I could make boolean flag as a class property, for whether the row still exists, and have each operation check that flag and throw an error if the row has been deleted. This maintains the oo structure of code, so I would have $objDbRow->delete(); But then I have to put checks at the beginning of each method. Or, I could implement a __destruct method that deletes the row. But that would seem counter-intuitive to me; if I saw in code unset($objDbRow); All I would suspect that's happening is that the object is being discarded, not that a row is being deleted. So that to me would seem like bad practice.

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  • Obj-c method override/polymorphism problem

    - by Rod
    Ok, so I'm using Objective-C. Now, say I have: TopClass : NSObject - (int) getVal {return 1;} MidClass : TopClass - (int) getVal {return 2;} BotClass : MidClass - (int) getVal {return 3;} I then put objects of each type into an NSMutableArray and take one out. What I want to do is run the getVal func on the appropriate object type, but when I put id a = [allObjects objectAtIndex:0]; if ([a isKindOfClass:[TopClass class]]) { int i; i = [a getVal]; } I get firstly a warning about multiple methods called getVal (presumably because the compiler can't determine the actual object type until runtime). But more seriously I also get an error "void value not ignored as it should be" and it won't compile. If I don't try and use the return from [a getVal] then it compiles fine e.g. [a getval]; //obviously no good if I want to use the return value It will also work if I use isMemberOfClass statements to cast the object to a class before running the function e.g. if ([a isMemberOfClass:[BotClass]) i = [(BotClass*) a getVal]; But surely I shouldn't have to do this to get the functionality I require? Otherwise I'll have to put in a statement for every single subclass, and worse have to add a new line if I add a new sub class, which rather defeats the point of method overriding doesn't it? Surely there is a better way?

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