Safety in php

[Defun]

HI, I whant to use a php form (http://phpforms.net/tutorial/html-basics/php-forms.html
) on my site. Is there any way to to validate and ban data coming from insecure sources?

[PeejAvery]

In the form processing, check for the HTTPS predefined variable.

if ($_SERVER['HTTPS'] == 'on') {/*...*/}