Pro WF

I started working with the new Microsoft WinFX technology stack early in the beta and CTP (Community Technology Preview) stage. The foundations in WinFX (Windows Presentation, Windows Communication, and Windows Workflow) have now finally made their way into a shipping Microsoft product: .NET 3.0. I actually started to learn and use all three of these foundations at the same time in my day job. Talk about a massive learning curve. While I was impressed with the flexibility and capabilities of Windows Presentation Foundation and Windows Communication Foundation, I was somehow inexplicably drawn to Windows Workflow Foundation (WF). WF isn't just a new way to implement a user interface, or a new way to communicate between applications and services. WF represents a completely new way to develop applications. It is declarative, visual, and infinitely flexible. It promotes a model that cleanly separates what to do from when to do it. This separation allows you to change the workflow model (the when) without affecting the what. Business logic is implemented as a set of discrete, testable components that are assembled into workflows like building blocks. Workflow isn't a new concept. But when Microsoft spends years developing a workflow foun- tion and provides it to us without cost, it is an event worth noting. Other workflow frameworks exist, but WF will soon become the de facto standard workflow framework for Windows applications.