How to return WorkflowInstanceId on CanCreateInstance on Receive Activity called via WCF

Question

I am using Windows Workflow Foundation 4.0.

I have got a console app running a WorkflowServiceHost with an EndPoint defined for a Receive Activity at beginning of a workflow.

I can call this endpoint in my client app, and pass in some parameters, but I can't see a way of returning the WorkflowInstanceId to my client app.

Answer 1

The WorkflowInstanceId isn't exposed to the SendReply, or any other standard, activity by default. You need to create a custom CodeActivity and return the InstanceId from the context object passed in. Next you can store the ID returned in a workflow variable and return that from the SendReply.