Book Image

Microsoft Windows Workflow Foundation 4.0 Cookbook

By : Andrew Zhu
Book Image

Microsoft Windows Workflow Foundation 4.0 Cookbook

By: Andrew Zhu

Overview of this book

Windows Workflow Foundation 4.0 (WF) is a significant part of .NET Framework 4.0. WF makes workflow technology available to every single programmer that uses the .NET Framework 4.0. It is easy to create long running and distributed programs using WF with the right knowledge. With this book, you will discover that working with workflows is easy. This book provides both step-by-step recipes and relevant background information. It covers all the important aspects of Windows Workflow Foundation 4.0. The best thing about this book is that all recipes are based on real-world experiences of Andrew Zhu. Andrew is a global WF and BizTalk technology support engineer for Microsoft. This book covers everything you need to know, when working with workflows. Get to grips with flow control activities, messaging, and transaction processes with easy to understand steps followed by explanations. You will quickly learn to use collection and custom WF activities and WF services.You will see recipes that illustrate integration of Windows Workflow with other applications such as WPF, ASP.NET, WCF service.Lastly, you will discover how easily you can customize W4 Designer with WF rule engine and others.
Table of Contents (15 chapters)
Microsoft Windows Workflow Foundation 4.0 Cookbook
About the Author
About the Reviewers

Loading a persisted workflow from the database

Developing long-running applications is one goal of WF4, and resuming a persisted workflow from the database is the key to long-running applications. In this task, we will create a Sequence workflow with a Delay activity. The workflow will be persisted when it is idle. We then press the Enter key and then the workflow will be resumed and will run until its end.

Getting ready

The SQL workflow instance store needs to be already in use. We can refer the Configuring the SQL persistence store section of this chapter.

How to do it...

  1. Create a workflow project:

    Create a new Workflow Console Application under solution Chapter06 and name the project as LoadingUpWorkflowFromPersistenceDB.

  2. Create a workflow:

    Open the Workflow1.xaml file, which is created by default, and create a simple workflow with a Delay activity.

    Set the Duration property of Delay activity to 1 second. Once the Delay activity is executed, the workflow will become idle and the whole...