I never thought of that, as I say, I'm new to PHP.
I've searched for a tutorial on doing this. Do you think the method here would be suitable.
Sorry for asking what is probably a naive question but I don't know php so don't know how to tell between good processes and bad processes.
Everybody has to start somewhere, right? We all did.
Client-side validation GOOD: it saves bandwidth and server CPU.
Server-side validation GOOD: it can't be bypassed.
Server-side validation BAD: you have to actually submit the form in order to validate the entries, which takes up network bandwidth and server CPU time/resources.
These are over-simplified, of course, but you get the basic principle.