- var_dump: documentation ( source)
- date_default_timezone_set: documentation ( source)
<?php date_default_timezone_set('Europe/London');
$now = new DateTime;
$utc = clone $now;
$now->setTimezone(new DateTimeZone('UTC'));
// utc
echo "UTC: {$utc->format('Y-m-d H:i')}\n";
// local
echo "Local: {$now->format('Y-m-d H:i')}\n\n";
var_dump($utc->format('U') == $now->format('U'));