dynamic controls accessed by javascript? RSS

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  gbrot

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  dynamic controls accessed by javascript?

  Mar 27, 2008 08:39 PM|LINK

  Is it possible to access a dynamically created textbox with a dynamically added javascript?  I noticed when you view the html on a page where there are dynamically created controls the dynamic controls don't show up in the html view... even though they show just fine on the page in normal view. Are the dynamic controls in some other hidden page or encrypted somewhere? 

  I'm guessing that's related to why I'm having trouble accessing the dynamic controls from my javascript function.

   Here's a snippet of what I'm doing: 
  

  TextBox txtDim = new TextBox();
  txtDim.ID = "txtDim" + i.ToString();
  txtDim.Attributes.Add("onBlur", "DecimalToFeet('" + txtDim.ID + "');");
  pnlDims.Controls.Add(txtDim);
  
  

   The javascript function is something like this:

  function DecimalToFeet(InputBoxID)
  {
    var InputControl = document.getElementById(InputBoxID);
    psDim = InputControl.value;
    ..bla bla bla...
    InputControl.value = psDim;
  }
  
  

    The javascript works fine when its called by a regular textbox control, but again, it's not doing anything from the dynamic control.
  
  Thanks!
  

   

  javascript ASP.NET 2.0 dynamic controls

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  whatispunk

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  Re: dynamic controls accessed by javascript?

  Mar 27, 2008 09:53 PM|LINK

  There are a couple subtle mistakes in your code.

  First: You must reference the ClientID property (or UniqueID) of your control in the Javascript.

  Second: You must add txtDim to the pnlDims.Controls collection in order for this ClientID to be created.

  1    TextBox txtDim = new TextBox();
  2    txtDim.ID = "txtDim" + i.ToString();
  4    pnlDims.Controls.Add(txtDim);
  3    txtDim.Attributes.Add("onBlur", "DecimalToFeet('" + txtDim.ClientID + "');");
  
  

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  gbrot

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  Re: dynamic controls accessed by javascript?

  Mar 28, 2008 02:48 PM|LINK

  Thanks for the response,

  I can see that I did have some bugs in that code.  I tried the changes you mentioned but I'm still having the same issue.  It just seems that I'm missing something when it comes to accessing dynamic controls.  The fact that I can't see the dynamic controls when I view the html source makes me think I need to do something drastically different to access them with javascript.
  

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  whatispunk

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  Re: dynamic controls accessed by javascript?

  Mar 28, 2008 04:42 PM|LINK

  If you use IEs View Source you won't see them, but if you use something FireFox's FireBug, or IEs IE Developer Toolbar, you will see the dynamic changes in real time.

  Remember: mark posts that helped you as the answer to aid future readers
  
  Why UpdatePanels Are Dangerous
  Why You Should Not Place Your Whole Site In An UpdatePanel
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  whatispunk

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  Re: dynamic controls accessed by javascript?

  Mar 28, 2008 04:44 PM|LINK

  Try using UniqueID instead of ClientID

  Remember: mark posts that helped you as the answer to aid future readers
  
  Why UpdatePanels Are Dangerous
  Why You Should Not Place Your Whole Site In An UpdatePanel
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  gbrot

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  Re: dynamic controls accessed by javascript?

  Mar 28, 2008 05:50 PM|LINK

  Using UniqueID fixed it!  Thanks, I would have never figured that out.

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  NC01

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  Re: dynamic controls accessed by javascript?

  Mar 28, 2008 06:03 PM|LINK

  Change to this:
   txtDim.Attributes.Add("onBlur", "DecimalToFeet(this);");

  And the JavaScript to:
   function DecimalToFeet(InputControl)
   {
    // var InputControl = document.getElementById(InputBoxID);

    // Rest of your code...

  NC...
  

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  gbrot

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  Re: dynamic controls accessed by javascript?

  Mar 28, 2008 06:26 PM|LINK

  actually that looks more like the right way to do this.  It works too!  Thanks for helping this javascript noob

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  NC01

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  Re: dynamic controls accessed by javascript?

  Mar 31, 2008 12:42 PM|LINK

  No problem.

  NC...