WF4实例对象转化成XAML文档

示例来自Microsoft Windows Workflow Foundation 4.0 Cookbook P29

1.  Create a workfow project:
Create a new Workfow Console Application under the Chapter01 solution and
name the project ConvertWFInstanceToXML. Delete the Workflow1.xaml fle
that is created by default.
2.  Write code to create the workfow and its host:
Open Program.cs fle and change the code as follows:
using System;
using System.Activities;
using System.Activities.Statements;
using System.Text;
using System.Xaml;
using System.Activities.XamlIntegration;

using System.IO;
namespace ConvertWFObjectToXML {
    class Program {
        static void Main(string[] args) {
            //Create a Workflow instance object             
ActivityBuilder ab = new ActivityBuilder();
            ab.Implementation = new Sequence()
            {
                Activities =
                {
                    new WriteLine{Text="Message from Workflow"}
                }
            };
            //Convert Workflow instance to xml string
            StringBuilder sb = new StringBuilder();
            StringWriter sw = new StringWriter(sb);
            XamlWriter xw =
                ActivityXamlServices.CreateBuilderWriter(
                new XamlXmlWriter(sw,
                                  new XamlSchemaContext()));
            XamlServices.Save(xw, ab);
            Console.WriteLine(sb.ToString());
        }
    }
}