Karl Shifflett recently published a fantastic article on CodeProject showing how to use his business entity framework in a WPF user interface. He explains how to establish validation rules both declaratively and imperatively, as well as how to generate business objects based on entity specifications stored in a database. He shows how to consume these objects and their validation errors in WPF. I found it particularly interesting how he ties in the business object validation errors with the parsing errors reported by the WPF databinding pipeline.
I highly recommend taking the time to read this monstrous article:
If you don’t have the time to read it now, at the top of the article there is a short video that shows his demo application in action. The video is great because he explains what his framework is doing while interacting with the UI that consumes it. Very nice, Karl!