Tip: How to pass initialize parameters to Silverlight application using ASP.NET 3.5 Silverlight control?

And what if you're using Silverlight in the ASP.NET MVC framework?

I'd like to pass in parameters from data in my model, but I don't want to use the code behind to set them, because in the RC1 of MVC ,ASPX code behind files will be no more !

If you try to pass in parameters in the ASPX file you get the following error:

 "Server tags cannot contain <% ... %> constructs"

The Silverlight itself can access the Url and get the QueryString, so you don't have to bother with passing it tio the HTML that invokes your Silverlight application. Using the HtmlPage class you are able to access the DOM and the url of the current page:

string queryParam = HtmlPage.Document.QueryString[<Key>];

For example you can do the following thing: In the App.xaml.cs add the following code in the Application_Startup handler:

private void Application_Startup( object sender, StartupEventArgs e )

{

    this.RootVisual = new Page();

    string queryParam = HtmlPage.Document.QueryString["key"];

    this.Resources.Add( <ResourceKey>, queryParam );

}

This way you can access the parameter through the application resources, which means it will be easyly accessible from both the Xaml and the Codebehind. The synthax for accessing the resource is:

XAML

<silverlightControl Property={StaticResource ResourceKey} />

C#

object parameter = ( ( App )Application.Current).Resources[ <ResourceKey> ];

That's it! ;)

If those params changed, how can I know it, from the App.xaml.cs