- var_dump: documentation ( source)
- preg_match: documentation ( source)
<?php
$s = "http://ad.zanox.com/ppc/?23012557C80290415&ULP=[[0000011028nubuck%20kaki&eurl=http%3A%2F%2Fwww.sarenza.nl%2Fbirkenstock-madrid-flor-w-s780328-p0000011028]]";
//var_dump(stristr($s,"_",true));
preg_match('\[\[(.+?)\]\]',$s,$matches);
var_dump($matches);
?>