- var_dump: documentation ( source)
- explode: documentation ( source)
- in_array: documentation ( source)
- ucfirst: documentation ( source)
<?php
$tz = 'europe/paris';
$truc = explode('/',$tz);
$tz = ucfirst($truc[0]).'/'.ucfirst($truc[1]);
echo "\n";
var_dump(in_array($tz, DateTimeZone::listIdentifiers()));