I have a textbox that accepts only numbers, no other characters. And I created the following function in the `keypress` method for that:

```
    private void txtRGIE_KeyPress(object sender, KeyPressEventArgs e)
    {
        if (!Char.IsDigit(e.KeyChar) && e.KeyChar != (char)8)
        {
            e.Handled = true;
        }
    }

```

Validation is working when I type, I can't type special characters or letters like I wanted. However, if I copy a numeric string that contains dots or other characters and paste it into the field, it accepts normally. For example, if you copy: 323.323 / 323 and paste into the field, it will accept. How do I validate the characters I paste, allowing only numbers?