Operation not supported in the WCF Test Client

Question

I created a WCF service and to the default service I added another operation contract on the main DataContract:

[OperationContract]
void DoSomething(UserData         


        

Answer 1

The WCF default expectation for a service call is request-response - WCF expects some kind of a response back.

If you want to use void (as in: no return value), you need to decorate those methods with

[OperationContract(IsOneWay = true)]
void DoSomething(UserData data);

to tell the WCF runtime not to expect any return value from the call

Read more about WCF: Working with One-Way Calls, Callbacks and Events here in MSDN Magazine.