Question

因此，我想做的是查找是否完全按下了空格键，而我想放开空格键，然后以大约10毫秒的延迟再次按下多个键。我已尝试阅读并理解此链接（https://msdn.microsoft.com/en-us/library/system.windows.forms.control.keypress.aspx），但它仍在混淆帮助吗？我是C＃的新手，但是我对Pascal有一些经验，我发现它非常相似（由于我的计算机不允许我更新到Windows 8.1，因此使用Visual Studio 2015）

Answer 1

10ms delay表示每秒100次，没人能做到。

关键事件按以下顺序发生：

KeyDown
KeyPress
KeyUp

事件KeyDown和KeyUp使用KeyEventArgs，而KeyPress是KeyPressEventArgs，

KeyEventArgs可以详细说明同时按下多少键。 KeyEventArgs.KeyCode是Keys，它是一个[Flags]枚举，它可以包含多个键，例如CTRL + SHift + F + G

如果您的热键是Ctrl + Shift + Space，则可以使用以下命令进行检查：

var hotkeyPressed = e.Control && e.Shift && e.KeyCode == Keys.Space;

如果您的热键是Ctrl + F10 + Space，则可以使用以下命令进行检查：

var hotkeyPressed = e.Control && e.KeyCode == (Keys.Space | Keys.F10);

但不要使用：

var hotkeyPressed = e.Control && e.KeyCode.HasFlag(Keys.F10) && e.KeyCode.HasFlag(Keys.Space); // e.KeyCode probably contains other flags

KeyPressEventArgs.KeyChar是一个字符串，请查看源代码，重点关注其注释

  [ComVisible(true)]
  public class KeyPressEventArgs : EventArgs
  {
    ...
    /// <summary>Gets or sets the character corresponding to the key pressed.</summary>
    /// <returns>The ASCII character that is composed. For example, if the user presses SHIFT + K, this property returns an uppercase K.</returns>
    public char KeyChar { get; set; }
    ...
  }

要使用哪个事件，取决于您的要求。这是KeyDown中的示例代码：

    private int counting = 0, limit = 10;
    private void txt_KeyDown(object sender, KeyEventArgs e)
    {
        if (!e.KeyCode.HasFlag(Keys.Space)) //check if your expected key is pressed
        {
            counting = 0;
            return;
        }
        //start counting
        counting++;

        if (counting > limit)
        {
            e.Handled = true;
            //do you business work, like: Send something somewhere

        }
        else
        {
            //do something else, like: show the number 'counting' in GUI
        }
    }

如果要限制下一个空格的时间跨度，请使用Timer

    private void txt_KeyDown(object sender, KeyEventArgs e)
    {
        timer1.Stop();
        if (!e.KeyCode.HasFlag(Keys.Space))
        {
            counting = 0;
            return;
        }
        //start counting
        timer1.Start();
        counting++;

        if (counting > limit)
        {
            e.Handled = true;
            //do you business work, like: Send something somewhere

        }
        else
        {
            //do something else, like: show the number 'counting' in GUI
        }
    }

    //timer1.Interval = 100; //100ms timeout. user has to press space again within 100ms
    private void timer1_Tick(object sender, EventArgs e)
    {
        counting = 0;
    }

按键检测并在C＃中发送

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