The Zend Developer Zone has a new tutorial posted today by Pierre dealing with one of the things becoming (and should have always been) important to PHP developers - filtering input. Specifically, it deals with using the Filter extension built into PHP 5 to take care of anything malicious or incorrect that the user might throw at the application.

Security becomes the top priority (or activity) of many PHP developers. Its place and importance keeps growing in every single project, open source or commercial. Every conference provides a talk about security and you can read PHP security on the magazine cover pages.

The article is broken down into different sections, including:

• Don't trust external data
• Why Filter?
• How does it work?
• Prerequises/Installation/Considerations

And, of course, what would a tutorial be without some examples. Pierre shows a simple form that filters, a sanitizing form, and some more complex processing using a callback.