- var_dump: documentation ( source)
<?php
$subject = new DateTime('2015-06-24 22:09:00');
var_dump(isset($subject->timezone));
$reflection = new ReflectionObject($subject);
foreach ($reflection->getProperties() as $prop) {
$prop->setAccessible(true);
$prop->setAccessible(false);
}
var_dump(isset($subject->timezone));