Allow to insert a value into a textbox that only accepts numbers

Question

I have a code that only allows numbers, comma and backspace to be entered in a textbox. But at the same time, I cannot insert text via ctrl + v. How can I do this?

private void textBox_KeyPress(object sender, KeyPressEventArgs e)
        {
            char number = e.KeyChar;
            if ((e.KeyChar <= 47 || e.KeyChar >= 58) && number != 8 && number != 44)
            {
                e.Handled = true;
            }
        }

Does this answer your question? [Handle a paste event in c#](https://stackoverflow.com/questions/15987712/handle-a-paste-event-in-c-sharp). Also, have you [read](https://learn.microsoft.com/en-us/uwp/api/windows.ui.xaml.controls.textbox.paste?view=winrt-19041) the documents? — Trevor, Apr 20 '21 at 20:22
Does this answer your question? [C# check characters in clipboard when paste into textbox](https://stackoverflow.com/questions/32730131/c-sharp-check-characters-in-clipboard-when-paste-into-textbox) — Charlieface, Apr 20 '21 at 21:17
Build a Custom Control derived from TextBox, override CreateParams and add to the Styles [ES_NUMBER](https://learn.microsoft.com/en-us/windows/win32/controls/edit-control-styles): now the TextBox only accepts numbers (and you can only paste in numbers). — Jimi, Apr 21 '21 at 01:08

score 0 · Answer 1 · answered Apr 20 '21 at 20:34

Considering that you are not checking e.Control property you are handling Ctrl+V in this event. e.Handled = !e.Control; will fix your code. Of course this will not prevent users from pasting in not numeric text. Probably better to handle OnTextChanged event and prevent entry that way.

Allow to insert a value into a textbox that only accepts numbers

1 Answers1