PHP Validation Demo
This form contains all the validation options that are offered by the PHP Validation library. To see how this works, download the zip file. Since the custom_alpha options are quite advanced and unlikely to be used that often (and because it's a pain figuring out a match for all of the cases!) I've filled in matching strings for those fields.
Standard form fields
Date fields
Numbers / alphanumeric fields
Length of field input
Password fields
Conditional (if-else) fields