$re = '/(?:[\?&][\w-]+=[\w=.|()+%-]+)+/m';
$str = '?tn_cid=280&tn_fk_specifications_planten_planttype=Groene%20kamer+planten|hangplanten|tuinplanten&tn_fk_ae-waterbehoefte=Weinig%20(2x%20per%20maand)&tn_fk_specifications_planten_plantheight=30%20-%2035%20cm&tn_fk_ae-hoogte-plant=Kleine%20planten%20(tot%2040%20cm)&tn_fk_ae-prijs=16.99-16.99';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php