Question

I have a multiline textbox which shouldn’t accept alphabets, numbers, newline(enter key) and backspace. In short, the textbox.Text shouldn’t be editable. But I do want the textbox to accept two shortcut keys – control and control+R. One way I can make the textbox un-editable is by making it read-only. But then the textbox wont accept any keystroke at all. In short, my shortcuts ( control and control+R) wont work( Control + R) with read-only method.

Can anyone help in this regard. That’s all I have to do.

One thing I could do here is not to make the textbox read-only and then restrict the characters(alphabets and digits) that could be inputted in the textbox. With this code:

    private void txtResult_KeyPress(object sender, KeyPressEventArgs e)
    {
        // only modifier keys, escape, enter, backspace etc is accepted now
        e.Handled = !char.IsControl(e.KeyChar);
    }

    private void txtResult_KeyDown(object sender, KeyEventArgs e)
    {
        if (e.Control == true)
        {
            if (e.KeyCode == Keys.R)
            {
                // do something
            }
            else
            {
                //do something
            }
        }

        if (e.KeyCode == Keys.Escape)
        {
            //do something
        }
    }

With this technique I can get the shortcuts(control and control+R) working. But the trouble with this method is that Enter and Backspace keys work as well making it possible to edit the text of textbox. How can I specifically restrict Enter and Backspace key being registered from the textbox, but let Control and Escape??

Answer 1

did you try SuppressKeyPress = true ?

private void textBox2_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.Control == true)
            {
                if (e.KeyCode == Keys.R)
                {
                    // do something
                }
                else
                {
                    //do something
                }
            }
            else
                e.SuppressKeyPress = true;


        }