c# - 短按和长按处理

Question

如果我短按键盘或长时间按键盘，我想执行 2 个不同的命令。如果我按住某个键，Windows 会向我发送多个 keyDown 和 KeyUp 事件。

现在。我这样做是为了处理“长按”

C++:

  if (pMsg->message == WM_KEYDOWN)
  {
    return keyboardManager->Execute( (KeyboardCommand)pMsg->wParam, BOOL (HIWORD(pMsg->lParam) & KF_REPEAT) == 0 ) )
  }

注意:pMsg 是一个 MSG 结构 (winuser.h)，而 KeyboardCommand 是一个具有虚拟键代码值的枚举

c#:

public Boolean Execute( KeyboardCommand _command, Boolean _first )
{
  switch(_command)
  {
    case (KeyboardCommand.myCommand):
              TimeSpan timeLapse = DateTime.Now - m_TimeKeyDown;
              if (_first)
              {
                m_TimeKeyDown = DateTime.Now;
                m_LongCommandExecuted = false;
              }
              else if (!m_LongCommandExecuted && timeLapse.TotalMilliseconds > 500)
              {
                m_LongCommandExecuted = true;
                handled = ExecuteAction();
              }


              break;
    case (KeyboardCommand.otherCommand):
              break;

  }
  return handled;
}

您知道如何处理“短按”吗？知道 KeyUp 是否是最后一个 keyUp(真正的 keyUp)可以解决我的问题。

Answer 1

您可以尝试以下操作。此示例仅挂接到窗体的 KeyDown 和 KeyUp 事件，因此您需要对其进行修改以满足您的需要。

//consider keys held less than one second a short keypress event
const double longThresholdMs = 1000.0;
Dictionary<Keys, DateTime> keyDownTimes = new Dictionary<Keys, DateTime>();

private void Form1_KeyDown(object sender, KeyEventArgs e)
{
    if (!keyDownTimes.ContainsKey(e.KeyCode))
    {
        keyDownTimes[e.KeyCode] = DateTime.Now;
    }
}

private void Form1_KeyUp(object sender, KeyEventArgs e)
{
    if (keyDownTimes.ContainsKey(e.KeyCode))
    {
        if (DateTime.Now.Subtract(keyDownTimes[e.KeyCode]).TotalMilliseconds > longThresholdMs)
        {
            Console.Out.WriteLine(e.KeyCode + " long press");
        }
        else
        {
            Console.Out.WriteLine(e.KeyCode + " short press");
        }

        keyDownTimes.Remove(e.KeyCode);
    }
}