- var_dump: documentation ( source)
- preg_match: documentation ( source)
<?php
$s = '!¾a’z„ ]¹g¤FÉæ[øšwô';
$b = 'kaskkasdkaksd';
foreach (array($s, $b, '') as $i) {
var_dump(preg_match('/^[\\x00\\x08\\x0B\\x0C\\x0E-\\x1F]*$/', $i, $match));
var_dump($match);
}