Microsoft AJAX returning JSON needs JavaScriptSerializer for deserialization

Microsoft AJAX  require JavaScriptSerializer to deserialize return object into JSON object. Use get-data() to extract object prior to deserialization.

Consider the code snip 

View

  <%using (Ajax.BeginForm("GetJSONGreeting", new AjaxOptions

                                                  {

                                                      OnComplete = "onComplete"

                                                  }))

...

 <script type="text/javascript">

           function onComplete(data) {

               var obj = Sys.Serialization.JavaScriptSerializer.deserialize(data.get_data());

               alert(obj.Message);

           }

    </script>

Controller

 public JsonResult GetJSONGreeting(string name)

        { 

            return Json( new {Message = string.Format("Hello {0} from JSON", name)});

        }