说明：   Windows Workflow Foundation(以下简称WWF)提供了一个编程框架和工具以开发和执行各种不同的基于工作流的应用程序，比如文档管理、线型的商业应用、贸易单据流程、IT管理、B2B应用以及消费者应用。 有状态的、持久化的、不间断运行的应用程序
(Windows Workflow Foundation (hereinafter referred to as WWF) provides a programming framework and tools to develop and implement a variety of workflow-based applications, such as document management, line of business applications, trade documentation processes, IT management, B2B applications, and consumer applications. Stateful, persistence, and continuous applications running)