How to make dynamically created textbox to accpet only input?

Question

I have dynamically created Textbox but not able to make it accept only numbers.How to do that?

Sam Hobbs · Answer

Derive a class from TextBox and put the following in it. Then use the derived class in your form. If you do not understand how to do that then you can probably add a handler for the KeyPress event for the TextBox and use the code in it. protected override void OnKeyPress(KeyPressEventArgs e) { base.OnKeyPress(e); string keyInput = e.KeyChar.ToString(); if (Char.IsDigit(e.KeyChar)) { return; } if (e.KeyChar == '\b') { return; } e.Handled = true; }

jasbirsingh chauhan · Answer

Thank you sir your code worked perfectly well.

Vulpes · Answer

One way would be to dynamically create a MaskedTextBox (rather than an ordinary TextBox) with a mask which only accepts numeric output. Another way would to write a KeyDown eventhandler which prevents anything other than numeric input being entered and then subscribe to this eventhandler dynamically. To do this in a robust way which prevents invalid stuff from being pasted in more than one decimal point being entered etc. isn't easy. A third way would be to accept that the user can input anything that (s)he likes but then validate it when control moves away from the textbox. This would again involve writing an eventhandler (for say the Leave event) and then subscribing to it dynamically. If the input proves to be invalid then a message could be displayed and the focus moved back to the textbox for amendment.