C# Numeric Only TextBox
Once in a while you find yourself needing to stop certain keypresses in a C# desktop application. I've found the best way is to handle this in the keypress event of a text box. This is some very small code that shows how to only allow numeric digits to be pressed. private void textBox_KeyPress( object sender, KeyPressEventArgs e ) { e.Handled = !char.IsDigit( e.KeyChar ); } Now if you want to allow other characters, like the decimal, etc you need to get a bit fancier. private void textBox_KeyPress( object sender, KeyPressEventArgs e ) { if( char.IsDigit( e.KeyChar ) || e.KeyChar == '.' ) { e.Handled = false; } else { ...