Not many workflows will live in isolation. Most workflows will need to communicate with either local or remote services to finish their job. In earlier chapters, we've looked at some of the basic building blocks for communication in Windows Workflow. These blocks include activities like the HandleExternalEvent
and WebServiceInput
activities.
In this chapter, we drill into more details about communication in Windows Workflow. We'll see how a host process can communicate with specific activities inside a workflow, and also examine the underlying queuing mechanism that makes communication work. Finally, we look at remote communications using web services. By the end of this chapter, we'll have the knowledge required to build a well-connected application.
We know that local communication services allow workflows to exchange data with their host process. In Chapter 3, we defined a service that raised a BugAdded
event to a running...