Activity is the essence of workflow; even the workflow itself is an Activity. WF4 provides some build-in activities that can be used directly in the workflow designer panel. But many times, we need to create our own activities—for example, an activity that can send e-mail to inform someone about finishing a task or any other important thing. To define our own activity, we should write a class that implements the root abstract Activity or one of its predefined subclasses.
The following is the activity modeling class hierarchy diagram:
This chapter intends to provide readers not only with some additional activities besides the built-in activities, but also with some concepts on how to build our own activities.
The other is the Workflow Console Application named
Workflow1.xaml, which is created by default. We will use these two projects throughout...