In this new tutorial from Developer.com, they take one of the popular PHP frameworks currently - CakePHP - and demonstrate how to make a simple form, complete with validation.
They start with a brief look at what CakePHP is and where you can get it from as well as the basics of input validation concepts. From there, it's on to the default validators that are included with the framework.
CakePHP offers several default validators capable of ensuring a value is a valid email address (VALID_EMAIL), year (VALID_YEAR), number (VALID_NUMBER), or non-empty (VALID_NOT_EMPTY).
Thanks to these built-in validation methods, some of the most common input validations are a snap. If you need a little something more, though, the framework has you covered there too with custom validators - as easy to implement as its preset counterparts. Finally, they show how to set custom messages in your form, both error and notification, and tie it all together in a simple form that validates the input for a "team name" field to ensure it's all alpha characters.