Question

请求进来，我的网络服务被调用。有时需要一个半小时才能完成处理。让我们说在此之后没有更多请求进入，因此应用程序池认为它处于非活动状态并在超时20分钟后关闭它。在我的网络服务中，我称之为Task.Facotry.StartNew().内的方法现在有一种方法可以防止应用程序池在任务状态尚未完成时关闭它吗？

Answer 1

有几种方法，但最简单的我发现只是启动一个单独的线程，该线程在无限循环中运行，带有某种退出标志条件，因此保持线程保持活动状态并且无限期地运行应用。像这样的调度程序很简单，可以创建：

/// <summary>

/// This is the manager class that handles running the email operation on a background thread

/// </summary>

public class Scheduler : IDisposable

{

    /// <summary>

    /// Determines the status fo the Scheduler

    /// </summary>        

    public bool Cancelled

    {

        get { return _Cancelled; }

        set { _Cancelled = value; }

    }

    private bool _Cancelled = false;





    /// <summary>

    /// The frequency of checks against hte POP3 box are 

    /// performed in Seconds.

    /// </summary>

    private int CheckFrequency = 180;



    EmailForwarder Forwarder = new EmailForwarder();



    AutoResetEvent WaitHandle = new AutoResetEvent(false);



    object SyncLock = new Object();



    public Scheduler()

    {



    }



    /// <summary>

    /// Starts the background thread processing       

    /// </summary>

    /// <param name="CheckFrequency">Frequency that checks are performed in seconds</param>

    public void Start(int checkFrequency)

    {

        this.Forwarder.DeleteMessages = App.Configuration.DeletePop3Messages;            



        // *** Ensure that any waiting instances are shut down

        //this.WaitHandle.Set();



        this.CheckFrequency = checkFrequency;

        this.Cancelled = false;



        Thread t = new Thread(Run);

        t.Start();

    }



    /// <summary>

    /// Causes the processing to stop. If the operation is still

    /// active it will stop after the current message processing

    /// completes

    /// </summary>

    public void Stop()

    {

        lock (this.SyncLock)

        {

            if (Cancelled)

                return;



            this.Cancelled = true;

            this.WaitHandle.Set();

        }

    }



    /// <summary>

    /// Runs the actual processing loop by checking the mail box

    /// </summary>

    private void Run()

    {

        this.Forwarder.LogMessage("...Starting Service",true);



        // *** Start out  waiting

        this.WaitHandle.WaitOne(this.CheckFrequency * 1000, true);



        while (!Cancelled)

        {

            if (App.Configuration.LogDetail)

                 this.Forwarder.LogMessage("...Checking mailbox...", true);



            if (!this.Forwarder.ProcessMessages())

                this.Forwarder.LogMessage("...Processing failed: " + Forwarder.ErrorMessage, false);

            else

            {

                if (App.Configuration.LogDetail)

                    this.Forwarder.LogMessage("...Processing completed", true);

            }



            // *** Http Ping to force the server to stay alive 

            this.PingServer();



            // *** Put in 

            this.WaitHandle.WaitOne(this.CheckFrequency * 1000,true);



        }



        this.Forwarder.LogMessage("...Shutting down service", true);

    }



    public void PingServer()

    {

        try

        {

            WebClient http = new WebClient();

            string Result = http.DownloadString(App.Configuration.PingUrl);

        }

        catch (Exception ex)

        {

            string Message = ex.Message;

        }

    }





    #region IDisposable Members



    public void Dispose()

    {

        this.Stop();

    }



    #endregion

}

阻止应用程序池关闭我的Web服务

1 个答案: