I've been away from HTML for awhile. I'd like to know if it is possible to validate text entered into a textbox on a form.
What I would like to do is to check to see if the user is entering the correct character string, say, 32p or 32P (or 33p or 33P). If the user enters the wrong string by mistake, I would like to pop up a messagebox, play a short sound and return and maintain focus on the textbox.
How involved is this?