短按和长按处理答案

【问题标题】：Short Press and long press handling短按和长按处理
【发布时间】：2014-11-17 17:03:01
【问题描述】：

如果我短按或长按键盘，我想执行 2 个不同的命令。如果我按住一个键，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)，KeyboardCommand 是一个带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;
}

你知道如何处理“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。

【问题讨论】：

标签： c# c++ windows keyboard-events

【解决方案1】：

您可以尝试以下方法。此示例仅挂钩到表单的 KeyDown 和 KeyUp 事件，因此您需要对其进行修改以满足您的需求。

//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);
    }
}

【讨论】：

【解决方案2】：

我找到了答案。

c++:

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

c#:

public Boolean Execute( KeyboardCommand _command, Boolean _first, Boolean _last, Boolean _keyDown )
    {
      if (_keyDown)
          {
            switch (_command)
            {
              case (KeyboardCommand.otherCommand):
                handled = ExecuteCommand();
                break;
            }
          }
      switch (_command)//Short press and long press events
          {
            case (KeyboardCommand.mycommand):
                if (_first)
                {
                  m_TimeKeyDown = DateTime.Now;
                  m_LongCommandExecuted = false;
                }
                else
                {
                  TimeSpan timeLapse = DateTime.Now - m_TimeKeyDown;
                  if (!m_LongCommandExecuted && timeLapse.TotalMilliseconds > 500)//long press
                  {
                    m_LongCommandExecuted = true;
                    handled = myLongcommand();
                  }

                  if (!m_LongCommandExecuted && _last)//short press
                  {
                    m_LongCommandExecuted = true;
                    handled = myShortcommand();
                  }
                }
                break;
          } 

   //some other jazz         

}

【讨论】：