No product would be complete today if it did not send or receive SOAP envelopes over HTTP. WF includes a number of activities that revolve around web services, both as a client and a server.
The InvokeWebService
activity can call an external web service. When we drop the activity into the workflow designer, the familiar Visual Studio Add Web Reference dialog box will appear. This same dialog appears when we add a web reference to any type of .NET project in Visual Studio. We merely need to browse to a Web Service Definition Language (WSDL) document with the description of the web service. Visual Studio will retrieve the WSDL and generate a proxy class for the web service. We can then configure the activity with the method name to invoke, and bind parameters to fields or properties in our workflow (see the screenshot).
The WebServiceActivity
includes Invoking
and Invoked
event handlers that fire before and after the web service call, respectively...