Book Image

Programming Windows Workflow Foundation: Practical WF Techniques and Examples using XAML and C#

By : Kenneth Scott Allen
Book Image

Programming Windows Workflow Foundation: Practical WF Techniques and Examples using XAML and C#

By: Kenneth Scott Allen

Overview of this book

Windows Workflow Foundation (WF) is a technology for defining, executing, and managing workflows. It is part of the .NET Framework 3.0 and will be available natively in the Windows Vista operating system. Windows Workflow Foundation might be the most significant piece of middleware to arrive on the Windows platform since COM+ and the Distributed Transaction Coordinator. The difference is, not every application needs a distributed transaction, but nearly every application does have a workflow encoded inside it. In this book, K Scott Allen, author of renowned .NET articles at www.odetocode.com, provides you with all the information needed to develop successful products with Windows Workflow. From the basics of how Windows Workflow can solve the difficult problems inherent in workflow solutions, through authoring workflows in code, learning about the base activity library in Windows Workflow and the different types of workflow provided, and on to building event-driven workflows using state machines, workflow communications, and finally rules and conditions in Windows Workflow, this book will give you the in-depth information you need. Throughout the book, an example "bug reporting" workflow system is developed, showcasing the technology and techniques used.
Table of Contents (14 chapters)
Programming Windows Workflow Foundation: Practical WF Techniques and Examples using XAML and C#
Credits
About the Author
About the Reviewer
Preface

How Do I Build Custom Activities?


There are two approaches to building a custom activity. One approach uses composition and the second approach uses derivation.

The composition approach is a similar experience to authoring a workflow. We use the designer to drag, drop, and configure activities inside a new custom activity, and then package the custom activity into an assembly for use in other workflow projects. The composition approach is a quick and easy path to reusable workflow components.

In the derivation approach, we derive a new activity from the Activity class. We can also derive from descendants of the Activity class to inherit more functionality. We can customize the design view, validation, serialization, and code-generation pieces of the activity. The derivation approach gives us the highest level of control and offers a path to extending Windows Workflow with custom code.

We will examine both of these approaches, but start with the composition approach.