title: Webservice expose a complex type to the client in wsdl
body: <p>I have (to make things easy) 2 classes 
  1) abstract class A
  2) inherited class B from A.</p>
  
  <p>now i'm using a method  "callMethod(A argument)"
  which is exposing my abstract class in the wsdl.</p>
  
  <p>But the problem is that on the client side i want to be able to know if A is B or something else. And i want to be able to reach the Class B which is not available since it's not in wsdl.</p>
  
  <p>I've tried KnownTypeAttribute and ServiceKnownTypeAttribute, but i'm not being able to getting it to work.</p>
  
  <p>Now of course i can create a dummy method that uses a parameter of type B, and thus resulting in class B being exposed in WSDL, but that's unprofessional.</p>
  
  <p>Any idea?
  Thanks a lot </p>