Most developers use “initParam” to get the QueryString value inside the Silverlight code; i.e at first they get the QueryString value inside the aspx.cs files and then pass that value as a initParam to the Silverlight code.
But we can get the queryString value directly from inside the Silverlight code.
1.Use this inside the code-behind of your XAML page
2. Get the QuerySting value like this.
Suppose in the webpage the address is http://localhost/registration.aspx?id=122
then we can get the “id” value inside the Silverlight code by using the following function: string ID= HtmlPage.Document.QueryString[“id”].ToString();