在keydown事件中传递了错误的键值 [英] False keyvalues are passed on keydown event

问题描述

我有一个MDI父母表格.当用户按下Enter键时，我希望该应用程序关闭.

I have a MDI parent form. When user presses Enter I want the Application to shut down.

我按如下检查keydown事件:

I check the keydown event as follows:

 private void MainForm_KeyDown(object sender, KeyEventArgs e)
 {

     if (e.KeyValue == (int)Keys.Enter) 
     {
                    Application.Exit();
     }
 }

现在，当我在窗体上没有任何可单击的控件(按钮，文本框等)时，它可以正常工作. e.KeyValue具有Enter键(13)的(int)值.但是，如果我在MDI表单上放置了一些按钮或文本框，则e.KeyValue会带来Alt密钥的键值，即18..为什么会这样?

Now it works fine, when I don't have any clickable controls on form (Button, TextBox etc). The e.KeyValue has the (int) value of Enter Key (13). But if I put some buttons or textboxes on to MDI Form, e.KeyValue brings the keyvalue of Alt Key i.e. 18. Why so ??

现在，如果我按Alt+Enter键，该表格将关闭；但不仅是在Enter键上

So now if I press Alt+Enter, the form closes; but not only on Enter Key

预先感谢

推荐答案

您需要尽快处理KeyPress.以下代码将为您工作:

You need to process the KeyPress a little sooner. The following code will work for you:

    protected override bool ProcessKeyPreview(ref System.Windows.Forms.Message m)
    {
        int _ENTER = 13;
        int _KEYUP = 257;
        if (m.Msg == _ENTER && (int)m.WParam == _KEYUP)
        {
            Application.Exit();
        }
        return base.ProcessKeyPreview(ref m);
    }

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