DispatcherHelper.DoEvents系列二：Button点击多次触发click解决方法

解决WPF中button按钮同时点击多次触发click的方法，供大家参考，具体内容如下

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DateTime lastClick = DateTime.Now; object obj = new object(); int i = 0; private void Button_Click(object sender, RoutedEventArgs e) {  this.IsEnabled = false;   var t = (DateTime.Now - lastClick).TotalMilliseconds;  i++;  lastClick = DateTime.Now;  System.Diagnostics.Debug.Print(t + "," + i + ";" + DateTime.Now);  Thread.Sleep(2000);    this.IsEnabled = true; }

以上代码并没法解决用户点击两次按钮触发两次的问题,因为ui线程是单线程的,所以这个这样会导致用户连续点击两次,会两秒后又调用Button_Click一次,输出如下:

1207.069,1;2017年4月19日 13:58:22
2055.1176,2;2017年4月19日 13:58:24

所以要在this.IsEnabled = false;后面强制界面刷新,代码如下:

private void Button_Click(object sender, RoutedEventArgs e)
  {
   this.IsEnabled = false;
   DispatcherHelper.DoEvents();
   var t = (DateTime.Now - lastClick).TotalMilliseconds;
   i++;
   lastClick = DateTime.Now;
   System.Diagnostics.Debug.Print(t + "," + i + ";" + DateTime.Now);
   Thread.Sleep(2000);
   this.IsEnabled = true;
  }
  public static class DispatcherHelper
  {
   [SecurityPermissionAttribute(SecurityAction.Demand, Flags = SecurityPermissionFlag.UnmanagedCode)]
   public static void DoEvents()
   {
    DispatcherFrame frame = new DispatcherFrame();
    Dispatcher.CurrentDispatcher.BeginInvoke(DispatcherPriority.Background, new DispatcherOperationCallback(ExitFrames), frame);
    try { Dispatcher.PushFrame(frame); }
    catch (InvalidOperationException) { }
   }
   private static object ExitFrames(object frame)
   {
    ((DispatcherFrame)frame).Continue = false;
    return null;
   }
  }

DispatcherHelper.DoEvents();这个方法会强制界面刷新，问题就解决了。