C#Threading.Suspend在Obsolete中,线程已被弃用？

Question

在我的应用程序中,我正在通过另一个线程(其他GUI线程)执行我的文件读取.有两个按钮分别挂起和恢复线程.

private void BtnStopAutoUpd_Click(object sender, EventArgs e)
        {
           autoReadThread.Suspend();
        }

private void BtnStartAutoUpd_Click(object sender, EventArgs e)
        {
           autoReadThread.Resume();  
        }

但我正面临这个警告,

Thread.Suspend已被弃用.请使用System.Threading中的其他类(如Monitor,Mutex,Event和Semaphore)来同步线程或保护资源. http://go.microsoft.com/fwlink/?linkid=14202

我怎么只运行单线程(而不是GUI线程),所以如何在这里应用同步或监控.

更新代码:

 class ThreadClass
{

    // This delegate enables asynchronous calls for setting the text property on a richTextBox control.
    delegate void UpdateTextCallback(object text);

    // create thread that perform actual task
    public Thread autoReadThread = null;

    public ManualResetEvent _event = new ManualResetEvent(true);

    // a new reference to rich text box
    System.Windows.Forms.RichTextBox Textbox = null;

    private volatile bool _run;

    public bool Run
    {
        get { return _run; }
        set { _run = value; }
    }

    public ThreadClass(string name, System.Windows.Forms.RichTextBox r1)
    {
        Textbox = r1;
        Run = true;
        this.autoReadThread = new Thread(new ParameterizedThreadStart(UpdateText));
        this.autoReadThread.Start(name);
    }

    private void UpdateText(object fileName)
    {

        //while (true)
        //{
        //    _event.WaitOne();
            while (Run)
            {

                if (Textbox.InvokeRequired)
                {
                    UpdateTextCallback back = new UpdateTextCallback(UpdateText);
                    Textbox.BeginInvoke(back, new object[] { fileName });
                    Thread.Sleep(1000);
                }

                else
                {
                    string fileToUpdate = (string)fileName;
                    using (StreamReader readerStream = new StreamReader(fileToUpdate))
                    {
                        Textbox.Text = readerStream.ReadToEnd();
                    }
                    break;
                //}
            }
        }       
    }

}

}

run是bool值,一个线程控制它(最初是真的)

并启动线程我在其他类中创建此类实例(此启动线程)

Answer 1

 //true makes the thread start as "running", false makes it wait on _event.Set()
  ManualResetEvent _event = new ManualResetEvent(true); 
  Thread _thread = new Thread(ThreadFunc);

  public void ThreadFunc(object state)
  {
      while (true)
      {
          _event.Wait();

          //do operations here
      }
  }


  _thread.Start();

  // to suspend thread.
  _event.Reset();

  //to resume thread
  _event.Set();

请注意,所有操作都在线程被"暂停"之前完成

你想要什么

private void ThreadFunc(object fileName)
{
    string fileToUpdate = (string)fileName;
    while (Run)
    {
        _event.WaitOne(); 

        string data;
        using (StreamReader readerStream = new StreamReader(fileToUpdate))
        {
            data = readerStream.ReadToEnd();
        }

        if (Textbox.InvokeRequired)
        {
            UpdateTextCallback back = new UpdateTextCallback(UpdateText);
            Textbox.BeginInvoke(back, new object[] { data });
        }

                Thread.Sleep(1000); 
    }       
}


private void UpdateText(string data)
{
    Textbox.Text = data;
}

Answer 2

Suspend和Resume被弃用的原因是因为没有保证在执行的什么时候线程将被挂起.这是件坏事.这里描述的问题以及解决方案.

解决方案应该包含WaitHandle(可能是AutoResetEvent或ManualResetEvent),您可以使用它来向autoReadThread发送信号以停止/启动.

Answer 3

我将使用监视器机制来实现暂停和恢复线程。Monitor.Wait 将导致线程等待 Monitor.Pulse。

private bool _pause = false;
private object _threadLock = new object();

private void RunThread()
{
    while (true)
    {
        if (_pause)
        {
            lock (_threadLock)
            {
                Monitor.Wait(_threadLock);
            }
        }

        // Do work
    }
}

private void PauseThread()
{
    _pause = true;
}

private void ResumeThread()
{
    _pause = false;
    lock (_threadLock)
    {
        Monitor.Pulse(_threadLock);
    }
}