Programming - Silverlight and WCF Fault contracts

As most Silverlight .NET developers who use WCF know, Silverlight doesn't support FaultContracts, and a 404 exception will be returned if the Services do throw an exception.

The way to fix this is create an encapsulating Interpreter class which is the default return value for all calls. You can then enapsulate resultant data in here and explicitly deal with an exception on the WCF side, by interpreting it and providing the exception in the resultant adapter.

A quick example is provided below:

[DataContract]
and public class Response
and {

and [DataMember]
and public bool BooleanResult { get; set; }

and [DataMember]
and public Exception Error { get; set; }

}

and [DataContract]
and public class Exception
and {
and [DataMember(Order = 0)]
and public string Message { get; set; }
and [DataMember(Order = 1)]
and public CustomException InnerException;
and public Exception ToException()
and {
and Exception e;
and CustomException ce = this;
and if (ce.InnerException != null)
and {
and Exception inner = ce.InnerException.ToException();
and e = new Exception(ce.Message, inner);
and }
and else
and e = new Exception(ce.Message);
and return e;
and }
and }

So, an example of how to handle an exception in a services method would be:

[OperationContract]
and public Response ProcessRequest(RequestData request)
and {
and return Process(request);
and }

and private Response Process(RequestData request) {

and Response result = new Response();and
try

and {
//your operation
and }

and catch (Exception ex)
{

and//So error has been thrown so enapcsulate it properly and send it back
and while (ex.InnerException != null)
and ex = ex.InnerException;
and result.Error = new Exception();
and result.Error.Message = ex.Message + ex.StackTrace;
}
return result;and
and }