- var_dump: documentation ( source)
- preg_split: documentation ( source)
<?php
$str = 'prijs=0,209&orderby=price&order=undefined&posts_per_page=undefined';
$array = preg_split('/[&]/' , $str);
foreach ($array as $a)
{
$values = preg_split('/[=]/' , $a);
$f[$values[0]][] = preg_split('/[,]/' , $values[1]);
}
var_dump($f);