How do I catch KeyUp event ? (sample of code, please)

问题

I need to catch KeyDown & especially KeyUp events for 1,2,3,4,5,6,7,8,9 keyboard buttons.

How does it do ?
I can catch KeyDown event but what about KeyUp ?
Please, provide some simple code.

回答1:

private void Form1_Load(object sender, EventArgs e)
{
    this.KeyUp += new KeyEventHandler(Form1_KeyUp);
}

void Form1_KeyUp(object sender, KeyEventArgs e)
{
    switch (e.KeyCode)
    {
        case Keys.NumPad1:
            break;
        case Keys.NumPad2:
            break;
            //...
    }
}

回答2:

     private void Form1_KeyUp(object sender, KeyEventArgs e)
    {
        if (e.KeyData == Keys.D1) // number 1
        {
            MessageBox.Show("Hello");
        }
    }

回答3:

If you need the logic to be exactly the same then you can hook up the same event handler to both the KeyUp and KeyDown events of the control you want to capture input on.

// this occurs as part of Initialisation via the designer or you can hook up manually
myControl.KeyDown += myControl_KeyChange;
myControl.KeyUp += myControl_KeyChange;
// ...

private void myControl_KeyChange(object sender, KeyEventArgs e)
{
    switch( e.KeyCode )
    {
        case Keys.1:
        {
            // handle the 1 key being pressed
            break;
        }        
        case Keys.2:
        {
            // handle the 2 key being pressed
            break;
        }
        // etc
    }
}

来源：https://stackoverflow.com/questions/3674810/how-do-i-catch-keyup-event-sample-of-code-please