Question

在按下键之后，将此代码向下append text发送到textBox。它为每个按键写入一行。请问是否有任何好的解决方案可以收集例如5键按下并将它们写在一行中？

          private void User_KeyPress(object sender, KeyPressEventArgs e)
    {
        textBox.AppendText(string.Format("You Wrote: - {0}\n", e.KeyChar));
        textBox.ScrollToCaret();
    }

例如，MOUSE不会被写成：

You Wrote: M; You Wrote: O; You Wrote: U; You Wrote: S; You Wrote: E

但输出将是：

You wrote: MOUSE

Answer 1

请勿致电textBox.AppendText。追加添加到现有字符串并组合它们。

你想写一些像textBox.Text = String.Format(...)

这样的东西

您应该在对象中创建一个私有变量，以跟踪所有字符并附加到该字符。拥有User_KeyPress方法的类应该具有如下变量：

private string _keysPressed = String.Empty;

现在在你的方法中你可以像这样追加和输出：

private void User_KeyPress(object sender, KeyPressEventArgs e)
{
    _keysPressed += e.KeyChar;
    textBox.Text = String.Format("You Wrote: - {0}\n", _keysPressed);
    textBox.ScrollToCaret();
}

Answer 2

可能是这样的：

string testCaptured = string.Empty;
int keyPressed = 0;

private void User_KeyPress(object sender, KeyPressEventArgs e)
{
    if (keyPressed < 5)
    {
        testCaptured += e.keyChar;
        keyPressed++;
    }
    else
    {
        textBox.Text = string.Format("You Wrote: - {0}\n", testCaptured);
        textBox.ScrollToCaret();
    }
}

Answer 3

您可以缓冲按键直到达到阈值，然后输出整个缓冲区的内容。

e.g。

Queue<char> _buffer = new Queue<char>();

private void User_KeyPress(object sender, KeyPressEventArgs e)
{
  _buffer.Enqueue(e.KeyChar);

  if(_buffer.Count > 5)
  {
    StringBuilder sb = new StringBuilder("You Wrote: ");
    while(_buffer.Count > 0)
      sb.AppendFormat(" {0}", _buffer.Dequeue());

    Console.WriteLine(sb.ToString());
  }
}

收集多个按键事件

3 个答案: