The issue while calling the Javascript from managed code RSS

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  mchlSync

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  The issue while calling the Javascript from managed code

  Dec 28, 2007 01:52 AM | LINK

  I'm trying to answer this post and I got one issue that I think it is a bug.

  What I'm trying to do is that trying to pass one value to Javascript function from Managed Code. As there is no parameter in EventArgs class, I created new class with parameter.It is working fine. then, The problem is that the property that I created "T Data" is not shown in Javascript. another thing that I notice is that sender is always null even we are sending the object.
  

  The new EventArgs class with parameters
  

  public class EventArgs<T> : EventArgs{
          private T _data;
  
          public EventArgs(T args)
          {
              _data = args;
          }
  
          public T Data
          {
              get
              {
                  return _data;
              }           
          }
      }

  Page.xaml.cs
  

  [Scriptable]
      public partial class Page : Canvas {

          public Page() {
           
              WebApplication.Current.RegisterScriptableObject("EntryPoint", this);           
              MouseLeftButtonDown += Page_MouseLeftButtonDown;
          }
          void Page_MouseLeftButtonDown(object sender, MouseEventArgs e) {
              if (CallbackToBrowser != null) {
                  CallbackToBrowser(this, new EventArgs<string>("my value"));
              }
          }

          [Scriptable]
          public event EventHandler CallbackToBrowser;

      }

  TestPage.html.js
  

  // JScript source code
  
  //contains calls to silverlight.js, example below loads Page.xaml
  function createSilverlight()
  {
      Silverlight.createObjectEx({
          source: "Page.xaml",
          parentElement: document.getElementById("SilverlightControlHost"),
          id: "SilverlightControl",
          properties: {
              width: "100%",
              height: "100%",
              version: "1.1",
              enableHtmlAccess: "true"
          },
          events: {
             onLoad: OnLoaded
          }
      });
        
      // Give the keyboard focus to the Silverlight control by default
      document.body.onload = function() {
        var silverlightControl = document.getElementById('SilverlightControl');
        if (silverlightControl)
        silverlightControl.focus();
      }
  }
  function OnLoaded(sender, args)
  {
      sender.Content.EntryPoint.CallbackToBrowser = onManagedCallback;
  }
  
  function onManagedCallback(sender, args)
  {
      if(args.Data){                                              //ERROR is here. args is nothing. sender is null.
          alert(args.Data);
      }  
  }
   

  Is that a bug or Did I miss something in my code? Thanks in advance.  

  (If this has answered your question, please click on "Mark as Answer" on this post. Thank you!)
  
  Regards,
  Michael Sync
  Silverlight MVP
  
  Blog : http://michaelsync.net
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  swildermuth

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  Re: The issue while calling the Javascript from managed code

  Dec 28, 2007 10:29 PM | LINK

  I am not sure why the sender is always null, that might be a bug.  But the bigger issue is the event argument.  To fix this you must mark the EventArgs as scriptable:

    [Scriptable]
    public class EventArgs<T> : EventArgs
    {
      private T _data;

      public EventArgs(T args)
      {
        _data = args;
      }

      [Scriptable]
      public T Data
      {
        get
        {
          return _data;
        }
      }
    }

  HTH

  Shawn Wildermuth
  MVP, Speaker and Author
  
  Web Workshop (HTML5/CSS/MVC4)
  San Fran, CA - Mar 28-30, 2012
  Dallas, TX: Apr 29-May 1, 2012
  https://agilitrain.com/Workshop/Info/Web_Workshop
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  mchlSync

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  Re: Re: The issue while calling the Javascript from managed code

  Dec 29, 2007 09:38 AM | LINK

  thanks. 

  (If this has answered your question, please click on "Mark as Answer" on this post. Thank you!)
  
  Regards,
  Michael Sync
  Silverlight MVP
  
  Blog : http://michaelsync.net