WPF 获取键盘点击值、组合键方式

string codeValue = "";

int InputCount = 0;
protected override void OnPreviewKeyDown(KeyEventArgs e)
{
    int keyValue = Convert.ToInt32(e.Key);
    if (keyValue == 156)
    keyValue = Convert.ToInt32(e.SystemKey);
    if (e.Key == Key.Up)
    {
         e.Handled = true;
         ScrollToVerticalOffset("up");
    }
    if (e.Key == Key.Down)
    {
         e.Handled = true;
         ScrollToVerticalOffset("down");
    }

　　
　　　//获取组合键，如Shift+F1【操作：按下Shift，同时按下F1】

　　　　if (e.KeyStates == Keyboard.GetKeyStates(Key.F1) && Keyboard.Modifiers == ModifierKeys.Shift)
　　　　{
　　　　　　codeValue = "Shift+F1";

　　　　}

　　//获取数字组合键，如200，201等【操作：依次按2 0 0 】
    if (e.Key.ToString().Contains("NumPad") || (keyValue >= 34 && keyValue <= 43))
    {
                string keyCode = e.Key.ToString().Substring(e.Key.ToString().Length - 1, 1);
                if (int.TryParse(keyCode, out int tmp))//如果转换失败（为false）时输出括号内容
                {
                    codeValue += keyCode;
                    InputCount += 1;
                }
                else
                {
                    codeValue = "";
                    InputCount = 0;
                }

                if (Core.Definition.QuickKeyManager.Instance.Exec(this.GetType(), 0, codeValue))
                {
                    e.Handled = true;
                    codeValue = "";
                    InputCount = 0;
                }

                if (InputCount == 3)
                {
                    codeValue = "";
                    InputCount = 0;
                }
                return;
  }
  if (Core.Definition.QuickKeyManager.Instance.Exec(this.GetType(), keyValue))
      e.Handled = true;

  codeValue = "";
  InputCount = 0;
  base.OnPreviewKeyDown(e);
}