This tutorial talks about easy field validation with Prototype.

I wanted a robust javascript validation library that was simple to implement and didn’t require me do any extra work other than creating the form. My favourite idea for a method of doing this is to utilise the field elements’ class attribute to indicate what sort of field it is and hence any validation requirements.

There are a few javascript libraries that implement that idea like wForms, but, since I’m currently hell-bent on re-writing all my javascript using Prototype, I thought I’d see how difficult or easy it would be to roll my own. Turns out that this is just the sort of thing that is easy with Prototype.

Demo of field validation using prototype

Download the code used in Demo

Read Full Tutorial…