public IAsyncResult BeginAnnounceOnline(EndpointDiscoveryMetadata discoveryMetadata, AsyncCallback callback, object state) { if (discoveryMetadata == null) { throw FxTrace.Exception.ArgumentNull("discoveryMetadata"); } using (new AnnouncementOperationContextScope(InnerChannel)) { return(InnerClient.BeginHelloOperation(discoveryMetadata, callback, state)); } }