Here is how to consume a JSON object in Silverlight 2.

1. Start with a JSON object:
   var Person = {
"firstName": "John",
"lastName": "Smith",
"address": {
"streetAddress": "21 2nd Street",
"city": "New York",
"state": "NY",
"postalCode": 10021
}
}
2. Create an entry point into Silverlight. You will need to add namespace System.Windows.Browser.
   
3. Next add C# classes to mirror the JSON object. It’s important to make sure the variables in the class are exactly how they appear in the JSON object, this is case sensitive.
   
4. Before adding the deserializing code, add references in your project for System.Runtime.Serialization, System.ServiceModel, and System.ServiceModel.Web.
   
5. Now that the proper references are made in the project, we can finally write the code that deserializes the JSON object. The class that does all the magic is System.Runtime.Serialization.Json.DataContractJsonSerializer.
   
6. Finally add some HTML and JavaScript to make this work. (To get the JSON object in a serialized form I am using the Prototype JavaScript library. That is where you’ll find the function Object.toJSON(). There are other ways to serialize a JSON object. Notably, if you are using the AJAX ASP.NET library, there is a function in there that does exactly the same thing as this call.)JavaScript
   function sendJSON(){ document.getElementById("SL").Content.Bridge.SendJSON(Object.toJSON(Person)); }
   HTML
   <input type="button" value="send JSON to SL" onclick="sendJSON()" id="btnSendJSON" />

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