workflow - 如何将 Windows 工作流作为 Web 服务 (.svc) 托管？

Question

我正在尝试将 Windows 工作流作为 Web 服务托管，下面是我构建的示例工作流，并希望作为 Web 服务(.svc)托管，您能否建议所需的步骤？

using System;
using System.ServiceModel.Activities;
using System.Activities;
using System.ServiceModel;
using System.Activities.Statements;

namespace DemoWF
{
    public class _25_LeaveRequest
    {
        public WorkflowService GetInstance()
        {
            WorkflowService service;
            Variable<int> empID = new Variable<int> { Name = "empID" };
            Variable<int> requestID = new Variable<int> { Name = "requestID" };

        Receive receiveLeaveRequest = new Receive
        {
            ServiceContractName = "ILeaveRequestService",
            OperationName = "ApplyLeave",
            CanCreateInstance = true,
            Content = new ReceiveParametersContent
            {
                Parameters ={
                    {"empID",new OutArgument<int>(empID)}
                }
            }
        };

        SendReply replyLeaveRequestID = new SendReply
        {
            Request = receiveLeaveRequest,
            Content = new SendParametersContent
            {
                Parameters ={
                            {"requestID",new InArgument<int>(requestID)},
                        },
            },
        };


        Sequence workflow = new Sequence()
        {
            Variables = { empID, requestID },
            Activities = {
                new WriteLine{Text="WF service is starting..."},
                receiveLeaveRequest,
                new WriteLine{
                    Text=new InArgument<string>(aec=> "Emp ID="+empID.Get(aec).ToString())
                },
                new Assign<int>{
                    Value=new InArgument<int>(5),
                    To=new OutArgument<int>(requestID)
                },
                new WriteLine{
                    Text=new InArgument<string>(aec=> "Request ID="+requestID.Get(aec).ToString())
                },
                replyLeaveRequestID
            },
        };

        service = new WorkflowService
        {
            Name = "AddService",
            Body = workflow
        };
        return service;
    }
}

现在，它是自托管的，如下所示

namespace DemoWF
{
    class Program
    {
        static void Main(string[] args)
        {
            LeaveRequest();
        }

        private static void LeaveRequest()
        {
            _25_LeaveRequest receiveAndReplyWorkflow = new _25_LeaveRequest();
            WorkflowService wfService = receiveAndReplyWorkflow.GetInstance();
            Uri address = new Uri("http://localhost:8000/WFServices");
            WorkflowServiceHost host = new WorkflowServiceHost(wfService, address);

            try
            {
                Console.WriteLine("Opening Service...");
                host.Open();

                Console.WriteLine("WF service is listening on " + address.ToString() + ", press any key to close");
                Console.ReadLine();
            }
            catch (Exception e)
            {
                Console.WriteLine("some thing bad happened" + e.StackTrace);
            }
            finally
            {
                host.Close();
            }
        }
    }
}

Answer 1

最快的方法是创建 WCF 工作流服务应用程序。



您将获得一个工作流设计器，您可以在其中拖放所需的事件:



如果您在 Visual Studio 中运行该项目，您将获得带有服务操作的自动生成的 WSDL:



它还将启动 Visual Studio 的 WCF 测试客户端工具:



您可以使用 Pick Branch 创建处理多种方法的基于工作流的服务。事件。每个分支都会有一个 Receive and Send Reply事件，接收事件移至 trigger部分和 action 中的发送回复事件部分。

每个触发器都针对服务的特定操作。在下面的例子中，我定义了两个操作:MyFirstOperation和 MySecondOperation .



下面是 WCF 测试客户端工具将通过工作流公开的多个操作显示的内容:



希望这能让你开始。建立基于工作流的 WCF 服务的主题可能会涉及很多。 :)