Hi there I understand that with WCF you decorate a Service Contract and expose members with OperationContract. Question is: if you create an operation contract for a method like: public SomeClass MyMethod() I understand that you decorate the SomeClass with DataContract attributes. Question - how does the client know about SomeClass? Does SomeClass need to be defined in the client code as well?

The answer – Yes.

:)

 

The client must have assembly with all operation contract methods defined.

There is two ways:

 

1 You can implement all service methods and classes in separated assembly (something like "common clases.dll") and both – the client and server will use it.

2 You can run you ready to work service on any place, and use "Add service reference " wizard in Visual Studio. For using this way you must have the MEX  (metadata exchange) endpoint and binding set up correctly.

2a – you can get Operation contract methods and Data contract classes from compiled service assembly (also from "add service reference" wizard.