Windows Workflow (WF): Passing the output of one activity as the input of the next in a sequence

Question

Hi, I am brand new to WF so forgive what might be a simple question.

I am creating multiple activities which will execute in a sequence and pass data down the chain. I know that one way to do this is to set a context variable in the parent Sequence from Activity A, and then read this value in Activity B (thus the output of A is effectively the input of B).

I'm fine using this technique, but if there is a way to directly declare that the input of Activity B should be the output of Activity A, I'd prefer this. I'm intrigued by this comment in the new Activity template:

"If your activity returns a value, derive from CodeActivity<TResult> and return the value from the Execute method."

What is the point of returning a value from an Activity? Can this return value be read somehow by the next Activity in the sequence, without using the shared parent's context?

Answer 1

If you use CodeActivity there is always an OutArument property called result. Whatever you return from the Execute() function is stored in there. You still need to hook the result up to a variable or other argument to use it in your workflow.