tailieunhanh - Lập trình .net 4.0 và visual studio 2010 part 20

WF4 là một thay đổi triệt để, do đó, ngay cả khi bạn là một WF kinh nghiệm phát triển hãy dành thời gian để làm việc theo cách của bạn thông qua ví dụ này là các nhà thiết kế đã thay đổi hoàn toàn và một số khái niệm mới đã được giới thiệu. | CHAPTER 6 WINDOWS WORKFLOW FOUNDATION 4 Existing WF3 Users WF has undergone some radical changes from version which unfortunately means that for those developers already utilizing WF3 are probably going to have to do some work to do to upgrade their applications. Statemachine Workflow Has Gone Probably the biggest problem you may encounter is in the initial release of WF there is no support for statemachine workflows. Microsoft seems undecided as to whether Statemachine will be introduced in future versions of WF but for now the answer is to utilize the new building blocks. Upgrade White Papers Microsoft has produced a number of excellent documents to assist you in upgrading to WF4 so your first step before you upgrade any applications should be to consult this link http .com fwlink LinkID 153313. WF3 Runtime Version 3 of the WF runtime will be included with .NET runtime so your WF3 should continue to run on the .NET framework. Interop Activity WF4 has a new activity called Interop discussed later in this chapter that can be used to run legacy WF code. This can serve as a halfway point until you are ready to upgrade your entire application. Is It Worth the Upgrade Probably. WF4 lays the groundwork for future enhancements and WF5 should not be such a radical upgrade. WF 4 offers superior performance 10 to 100 times quicker a much improved designer and many other changes that we will discuss in this chapter. Kenny Wolf architect on WCF and WF team at PDC 08 noted that some customers in the early adopter program reduced their code by 80 percent by moving to WF4. All Change WF4 is a radical change so even if you are an experienced WF developer please take the time to work your way through this example as the designer has changed completely and a number of new concepts have been introduced. 133 CHAPTER 6 WINDOWS WORKFLOW FOUNDATION 4 Hello WF 4 We will write a simple workflow that will handle a booking for a movie theatre. Our example workflow .