Numbers only Textbox

Question

Hi everyone.
I have actually managed to make it so the user can only enter numbers 0-9 and backspace (incase they want to delete the number entered) in the textbox.
I want to know how I can limit the user to only entering numbers between 0-255. I have changed textbox property MaxLength to 3, but the user can still  enter numbers from 0-999.
Thanks in advance.
George.

Sam Hobbs · Answer

It is difficult or impossible to do that effectively while the data is being entered, but you could validate the data when the textbox loses focus.

Mike Gold · Answer

I would consider using the NumericUpDown Control because it already has this functionality.  You can set maximum and minimum values and it will restrict numbers as well.  The other possibility is to create your own class, override the OnKeyDown, and do your limitations here, but this is much more involved.