如何使线程等到另一个线程完成启动

Question

我正在使用DispatcherTimer调用一个方法来执行在不同的线程。我正在运行一个简单的程序，不需要担心无效率。如何让UI线程等待DispatcherTimer完成，同时仍然允许DispatcherTimer线程更改UI？

*我知道这可能是半重复性的，但我所看到的例子都是特定案例。由于

private void spinButton_Click(object sender, RoutedEventArgs e) 
    { 

     minSelTextBlock.Text = ""; 

      Index = 0; 
      maxIndex = rnd.Next(40, 60); 
      DispatcherTimer timer; 
      timer = new DispatcherTimer(DispatcherPriority.Normal); 
      timer.Interval = TimeSpan.FromMilliseconds(60); 
      timer.Tick += new EventHandler(TimerTick); 
      timer.Start(); 
      selPeople[x].IsCheck = false; 
      displayCount++; 

      Index = 0; 
      maxIndex = rnd.Next(40, 60); 
      timer = new DispatcherTimer(DispatcherPriority.Normal); 
      timer.Interval = TimeSpan.FromMilliseconds(60); 
      timer.Tick += new EventHandler(TimerTick); 
      timer.Start(); 
      selPeople[x].IsCheck = false; 
      displayCount++; 

      displayImage2b.Source = new BitmapImage(new Uri(selPeople[0].ImgPath));   
    } 

private void TimerTick(object sender, EventArgs e) 
    { 
     minSelTextBlock.Text = ""; 

     x = rnd.Next(0, selPeople.Count); 
     while (x == temp) 
     { 
      x = rnd.Next(0, selPeople.Count); 
     } 

     if (displayCount == 0) 
      displayImage1a.Source = new BitmapImage(new Uri(selPeople[x].ImgPath)); 
     if (displayCount == 1) 
      displayImage2a.Source = new BitmapImage(new Uri(selPeople[x].ImgPath)); 


     if (++Index >= maxIndex) 
     { 
      ((DispatcherTimer)sender).Stop(); 
     } 
     Index++; 
     temp = x; 
    } 

基本上我需要TimerTick得到selPeople [X] .IsCheck =假前的最后x值，因为重点是去除刚刚从列表中选择的项目。

Answer 1

如果你想调用者的方法来等待这就是所谓的方法的结果，你可以使用异步/等待，在.NET 4.5可

你可以做这样的事情：

private async void spin() 
    { 

     minSelTextBlock.Text = ""; 

      Index = 0; 
      maxIndex = rnd.Next(40, 60); 
      DispatcherTimer timer; 
      timer = new DispatcherTimer(DispatcherPriority.Normal); 
      timer.Interval = TimeSpan.FromMilliseconds(60); 
      timer.Tick += new EventHandler(StartTicker); 
      timer.Start(); 
      selPeople[x].IsCheck = false; 
      displayCount++; 

      Index = 0; 
      maxIndex = rnd.Next(40, 60); 

      await Ticker(); 

      selPeople[x].IsCheck = false; 
      displayCount++; 

      displayImage2b.Source = new BitmapImage(new Uri(selPeople[0].ImgPath));   
    } 


    Private Task<void> StartTicker() 
    { 
    Task.Run<void>(()=>Ticker()); 
    } 

private void Ticker() 
    { 
     while(your condition is true) 
     { 
     minSelTextBlock.Text = ""; 

     x = rnd.Next(0, selPeople.Count); 
     while (x == temp) 
     { 
      x = rnd.Next(0, selPeople.Count); 
     } 

     if (displayCount == 0) 
      displayImage1a.Source = new BitmapImage(new Uri(selPeople[x].ImgPath)); 
     if (displayCount == 1) 
      displayImage2a.Source = new BitmapImage(new Uri(selPeople[x].ImgPath)); 


     if (++Index >= maxIndex) 
     { 
      break; 
     } 
     Index++; 
     temp = x; 
     Thread.Sleep(60); 
     } 
    } 

而不是定时器我已经使用了一个While Loop和Thread.Sleep()这是你的计时器相同。

如果您想了解异步/等待我真的建议this

再见我还没有编这个代码的方式。所以它可能有一些语法或其他错误。