WF 4.0 What is different from 3.X
I’m playing with WF 4.0 at the moment and made a list what’s changed compared with WF 3.X.
Some features were already known since the PDC but I’m trying to create a nice overview list.
I will change this post as I play further with it.
- WF 4.0 is completely rewritten. So you can’t upgrade your WF 3.X workflows to WF 4.0. All activities and the runtime is new. Some activities are familiar but there are many new ones.
- You can still use your WF 3.X custom activities. This can be done via the new Interop activity.
- StateMachine workflows do not exists anymore. Only Seqential and a new type called FlowChart.
- Code and XAML based workflows are possible, but code based workflows do not have a designer.
- It’s possible to Unit Test Activities (workflows are activities too)
- Activities doesn’t have to be executed via a workflow. Activities can be executed in code also. Which makes reuse of activities more interesting.
- Not possible to make properties on your workflow. Instead of this there are variables and arguments now. Variables represent the storage of data. Arguments represent the flow of data into and out of an activity. Variables have a scope. The activity selected provides the scope. There are 2 new views in Visual Studio to manage the variables and arguments.
- On all kinds of activities, expressions are possible. Like the if statement on a If Activity. Expressions are program statements, a string value or .NET code. This expressions are written in VB!. This means capitalization does not matter, comparison is performed using a single equals sign instead of “==”, and the Boolean operators are the words "and" and "or" instead of the symbols "&&" and "||".
- ExceptionHandling is not arranged through a separate designer anymore. There is a TryCatch activity now. (which has a finally also)
- The parallel activity is truly executing parallel now
- Correlation can be setup with your own identifier (content based correlation)
Much more to come…
Part 2 continues the list