在覆盖 ProcessCmdKey EventHandler 时跳过 KeyDown [英] Skipping KeyDown On Override ProcessCmdKey EventHandller

问题描述

我通过按下箭头键在文本框上有一个简单的增量，如下所示.

I have a simple increment on textbox by pressing down arrow key which are as below.

protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
{

     if (keyData == Keys.Down)
     {

           int c = int.Parse(textBox1.Text);
           c++;
           textBox1.Text = c.ToString();


     }
 }

以上适用于按双下箭头键而不是单按下箭头键.

The above works on pressing double down arrow key instead of single pressing down arrow key.

注意:上面的代码在 UserControl 上.我已经在表单 keydown EventHandler 上的简单 winform 应用程序上进行了尝试，并且效果很好.

Note: The above code is on UserControl. And I have tried it on simple winform application on form keydown EventHandller and the same is works fine.

如何克服?.

推荐答案

您需要处理之前存在的其他命令，并在处理您要查找的命令时返回.尝试将其更改为此，看看是否有帮助:

You'll need to handle other commands that existed before and return when you handle ones you are looking for. Try changing it to this and see if that helps:

protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
{
   if (msg.WParam.ToInt32() == (int)Keys.Down)
   {
      int c = int.Parse(textBox1.Text);
      c++;
      textBox1.Text = c.ToString();
      return true;
   }
   return base.ProcessCmdKey(ref msg, keyData);
}

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