处理C#中的keyevent [英] handle keyevent in c#

问题描述

我需要在c#项目中处理一个事件，以便每当按下该键时都应该发生该事件.为此，我尝试了以下示例代码，但它不起作用并且也没有显示任何错误.

Hi,
I need to handle an event in my c# project such that whenever the key is pressed the event should occur.For that I tried with a following sample code but its not working and neither shows any error.

private void Form1_KeyDown(object sender, System.Windows.Forms.KeyEventArgs e)
       {
           if (e.KeyCode == Keys.Space)
           {
               MessageBox.Show("key pressed");
           }
       }

任何解决方案都将真正有很大帮助.
谢谢.

Any solution would really be a great help.
Thank you.

推荐答案

仅在表单级别处理键盘事件而不使其他控件能够接收键盘事件，请在表单中设置KeyPressEventArgs.Handled属性. ■true的KeyPress 事件处理方法.在此处阅读此信息 [

To handle keyboard events only at the form level and not enable other controls to receive keyboard events, set the KeyPressEventArgs.Handled property in your form''s KeyPress event-handling method to true. Read about this here[^].

执行以下操作:

将表单的KeyPreview设置为true，以便表单可以捕获空格键.

Do the following:

Set the form''s KeyPreview to true so that the form can capture the Spacebar.

this.KeyPreview = true;

然后使用以下形式的KeyDown事件:

Then use the KeyDown event of the form:

this.KeyDown += new KeyEventHandler(Form1_KeyDown);

void Form1_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.KeyCode == Keys.Space)
            {
                MessageBox.Show("key pressed");
            }
        }

现在应该可以工作了.

并重要地设置

Should work now..

And importantly set

this.KeyPreview = true;

在表单的构造函数上，或者只是使用表单设计器并将KeyPreview参数设置为true.

最后看看此处 [

on your form''s constructor, or simply use the form designer and set the KeyPreview parameter to true.

And finally have look Here[^]

如果您想处理表单上的事件，请尝试此

If you wants to handle events on form then try this

<pre lang="cs">public partial class Form1 : Form<br />
{<br />
    public Form1()<br />
    {<br />
        InitializeComponent();<br />
        KeyPreview = true;<br />
        KeyDown += new KeyEventHandler(Form1_KeyDown);<br />
    }<br />
<br />
    void Form1_KeyDown(object sender, KeyEventArgs e)<br />
    {<br />
        System.Diagnostics.Debug.Write(e.KeyCode);<br />
    }<br />
}</pre>

对于特定控件，您必须处理该控件上的事件.

例如:



处理KeyDown事件，以确定输入到控件中的字符类型.

And for specific control you must handle event on that control.

For example :



Handle the KeyDown event to determine the type of character entered into the control.

private void textBox1_KeyDown(object sender, System.Windows.Forms.KeyEventArgs e)
{
    // Initialize the flag to false.
    nonNumberEntered = false;

    // Determine whether the keystroke is a number from the top of the keyboard.
    if (e.KeyCode < Keys.D0 || e.KeyCode > Keys.D9)
    {
        // Determine whether the keystroke is a number from the keypad.
        if (e.KeyCode < Keys.NumPad0 || e.KeyCode > Keys.NumPad9)
        {
            // Determine whether the keystroke is a backspace.
            if(e.KeyCode != Keys.Back)
            {
                // A non-numerical keystroke was pressed.
                // Set the flag to true and evaluate in KeyPress event.
                nonNumberEntered = true;
            }
        }
    }
}

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