Wednesday, December 05, 2007

PageFlow, WorkFlow classes and Designer

Widnows WorkFlow Foundation provides an in-process workflow engine for many classes with visual work flow process in design mode in VS, such as Sequential WorkFlow, Machine WorkFlow, Activities, PageFlow, and so on.

By using the visual designer, you can easily define work flow, process item relationships and constrains as a work flow class. In addition to WWF core WorkFlow classes, other third parties or organizations or open source groups (such as PnP) adds other useful WorkFlow classes. The APS.NET solution I have been working on includes a project with PageFlow class.

The PageFlow class is defined within Microsoft.Practices.PageFlow.WorkFlowFoundation.dll by Microsoft Patterns and Practices group. The problem I encountered is that after I created the project by using Guidance Package Manger Recipe of Add PageFlow Project, I got an error message when I tried to open PageFlow1.cs in design mode in VS, but I don't have problem to compile the project. It looks like that its related designer class is not available.

Actually, the designer class is Microsoft.Workflow.VSDesigner.dll. I have to search for this file first. Then I copy this file to the folder where ...WorkFlowFoundation.dll file sits. After making the designer class directly available to the owner assembly, I can see the class in design mode in VS after I re-open the VS again.