Content correlation in hosted WF services seems daunting but is surprisingly simple to use with the available designer support. Content correlation uses data from the workflow to link (correlate) multiple WCF service operations to the same hosted workflow instance. Content correlation is different to context correlation where WCF communication down at the binding level handles correlation. There is unfortunately a lack of detailed examples available on how to get content correlation to work. This post aims to fill that gap.
I have an account registration scenario where the first service operation is to request a new account. The request needs to provide a first name, last name, email address and a password. The register account workflow will run some validation logic and then send an email to the email address with a link back to a website for confirmation.