c# - 提高 Windows Workflow 的速度

Question

我有以下代码可以让我执行工作流。这可以重复调用。而且经常是。它也存在于网络服务中，因此可能同时有多个调用。这目前有效。但它很慢，因为每次实例化一个 WorkflowRuntime 都非常慢。

我该如何改进？

public class ApprovalWorkflowRunner : IApprovalWorkflowRunner
{
    private static ILogger Logger { get; set; }
    private static IRepository Repository { get; set; }

    public ApprovalWorkflowRunner(ILogger logger, IRepository repository)
    {
        Logger = logger;
        Repository = repository;
    }

    public Request Execute(Action action)
    {
        var request = new Request();

        using (var workflowRuntime = new WorkflowRuntime())
        {
            workflowRuntime.StartRuntime();
            var waitHandle = new AutoResetEvent(false);
            workflowRuntime.WorkflowCompleted += ((sender, e) =>
                                                    {
                                                        waitHandle.Set();
                                                        request = e.OutputParameters["gRequest"] as Request;
                                                    });
            workflowRuntime.WorkflowTerminated += ((sender, e) =>
                                                    {
                                                        waitHandle.Set();
                                                        Logger.LogError(e.Exception, true, action.Serialize());
                                                    });

            var parameters = new Dictionary<string, object>
                                {
                                    {"RepositoryInstance", Repository},
                                    {"RequestID", action.RequestID.ToString()},
                                    {"ActionCode", action.ToString()}
                                };

            var instance = workflowRuntime.CreateWorkflow(typeof (ApprovalFlow), parameters);
            instance.Start();
            waitHandle.WaitOne();
        }

        return request;
    }
}

理想情况下，我想保留一份 WorkflowRuntime。但是由于我在 CreateWorkflow 函数和 WorkflowCompleted 事件中传递其他对象，所以我不知道它是如何工作的。

...我是不是漏掉了一些简单的东西，很有可能我的大脑没有告诉我的 body 它今天没有出现在工作中。

Answer 1

一个运行时可以同时运行多个工作流。根据此处的答案:

该页面显示了我将在下面包含的 WorkflowRuntime 工厂的一些代码，我相信这些代码最初取自 Windows Workflow Foundation Step by Step Book

public static class WorkflowFactory
{
    // Singleton instance of the workflow runtime
    private static WorkflowRuntime _workflowRuntime = null;

    // Lock (sync) object
    private static object _syncRoot = new object();

    /// <summary>
    /// Factory method
    /// </summary>
    /// <returns></returns>
    public static WorkflowRuntime GetWorkflowRuntime()
    {
        // Lock execution thread in case of multi-threaded
        // (concurrent) access.
        lock (_syncRoot)
        {
            // Check for startup condition
            if (null == _workflowRuntime)
            {
                // Provide for shutdown
                AppDomain.CurrentDomain.ProcessExit += new EventHandler(StopWorkflowRuntime);
                AppDomain.CurrentDomain.DomainUnload += new EventHandler(StopWorkflowRuntime);

                // Not started, so create instance
                _workflowRuntime = new WorkflowRuntime();

                // Start the runtime
                _workflowRuntime.StartRuntime();
            } // if

            // Return singleton instance
            return _workflowRuntime;
        } // lock
    }

    // Shutdown method
    static void StopWorkflowRuntime(object sender, EventArgs e)
    {
        if (_workflowRuntime != null)
        {
            if (_workflowRuntime.IsStarted)
            {
                try
                {
                    // Stop the runtime
                    _workflowRuntime.StopRuntime();
                }
                catch (ObjectDisposedException)
                {
                    // Already disposed of, so ignore...
                } // catch
            } // if
        } // if
    }
}

你只需调用

WorkflowFactory.GetWorkflowRuntime();

编辑:好的，对不起。您可以尝试检查实例是否是您期望的实例，如果不是则返回。请注意此代码未经测试，只是为了让大家理解这个想法。

public class ApprovalWorkflowRunner : IApprovalWorkflowRunner
{
    private static ILogger Logger { get; set; }
    private static IRepository Repository { get; set; }

    public ApprovalWorkflowRunner(ILogger logger, IRepository repository)
    {
        Logger = logger;
        Repository = repository;
    }

    public Request Execute(Action action)
    {
        var request = new Request();

        var workflowRuntime = WorkflowFactory.GetWorkflowRuntime();

        workflowRuntime.StartRuntime();
        var waitHandle = new AutoResetEvent(false);
        WorkflowInstance instance = null;
        workflowRuntime.WorkflowCompleted += ((sender, e) =>
                                                {
                                                    if (e.WorkflowInstance != instance) return;
                                                    waitHandle.Set();
                                                    request = e.OutputParameters["gRequest"] as Request;
                                                });
        workflowRuntime.WorkflowTerminated += ((sender, e) =>
                                                {
                                                    if (e.WorkflowInstance != instance) return;
                                                    waitHandle.Set();
                                                    Logger.LogError(e.Exception, true, action.Serialize());
                                                });

        var parameters = new Dictionary<string, object>
                            {
                                {"RepositoryInstance", Repository},
                                {"RequestID", action.RequestID.ToString()},
                                {"ActionCode", action.ToString()}
                            };

        instance = workflowRuntime.CreateWorkflow(typeof (ApprovalFlow), parameters);
        instance.Start();
        waitHandle.WaitOne();

        return request;
    }
}