- var_dump: documentation ( source)
- preg_replace: documentation ( source)
<?php
$c = 'test /*sdiznkngu ehfsdfhisdu fjaoaj* jrdgjnfsdgjuhd fihj/ fpreg_replace("/fgs\/*dh/")göl/*kmfdnn*/ idu//fhijk/*sdm gkj*/ solala
//gfkjlgn fdkughnsmdg f/*dhgsfd*/
joar
';
$c = preg_replace('![^\\\]\/\*(.*?)\*\/!si','',$c);
var_dump($c);