UI线程块

我创建了一个简单的 WPF 应用程序，并向默认窗口添加了一个按钮。当我单击按钮时，会调用一个模拟的长工作方法（使用 Thread.Sleep(15000) 进行模拟）。我试图使按钮异步执行，但是尽管遵循在线示例，按钮和整个窗口都会在我锁定时立即锁定单击并保持该状态直到 Thread.Sleep(...) 完成。

有什么想法为什么会发生这种情况吗？

这是代码：

private void button1_Click(object sender, RoutedEventArgs e)
{
   DoSomeAsyncWork();
}

private void DoSomeAsyncWork()
{
     System.Windows.Threading.Dispatcher.Run();
     Thread thread = new System.Threading.Thread(
         new System.Threading.ThreadStart(
          delegate()
          {
               Application.Current.Dispatcher.BeginInvoke(DispatcherPriority.Normal, new Action(() => Thread.Sleep(15000)));
          }
        ));
     thread.Start();
}

您正在将长操作放回到 UI 线程中。让我评论一下你的例子：

Thread thread = new System.Threading.Thread( 
    new System.Threading.ThreadStart( 
        delegate() { 
            // here we are in the background thread

            Application.Current.Dispatcher.BeginInvoke(DispatcherPriority.Normal, 
                new Action(() => {
                    // here we are back in the UI thread
                    Thread.Sleep(15000);
                })); 
      } 
    )); 

因此，您应该像这样修改您的示例：

Thread thread = new System.Threading.Thread( 
    new System.Threading.ThreadStart( 
        delegate() { 
            // here we are in the background thread

            Thread.Sleep(15000);  // <-- do the long operation here

            Application.Current.Dispatcher.BeginInvoke(DispatcherPriority.Normal, 
                new Action(() => {
                    // here we are back in the UI thread

                    // do stuff here that needs to update the UI after the operation finished
                })); 
      } 
    )); 

正如其他人提到的，使用 BackgroundWorker 类更容易。这是一个例子：

private void DoSomeAsyncWork()   
{   
    BackgroundWorker bw = new BackgroundWorker();

    bw.DoWork += (sender, args) => {
        // do your lengthy stuff here -- this will happen in a separate thread
        Thread.Sleep(15000);
    }

    bw.RunWorkerCompleted += (sender, args) => {
        if (args.Error != null)  // if an exception occurred during DoWork,
            MessageBox.Show(args.Error.ToString());  // do your error handling here

        // do any UI stuff after the long operation here
        ...
    }

    bw.RunWorkerAsync(); // start the background worker
}