IAsyncResult IAnnouncementContract11.BeginHelloOperation(HelloMessage11 message, AsyncCallback callback, object state)
 {
     return(new HelloOperation11AsyncResult(this, message, callback, state));
 }
 void IAnnouncementContract11.HelloOperation(HelloMessage11 message)
 {
     Fx.Assert("The [....] method IAnnouncementContract11.HelloOperation must not get invoked. It is marked with PreferAsyncInvocation flag.");
 }