timezone - Convert time and date from one time zone to another in PHP

Question

Basically what I need is an script that, when provided with a time and a timezone can return the time in another time zone.

My main issues are:

• Where to get the time offset from GMT from - is there a public database available for this?
• How to also take into consideration the daylight saving time (DST) differences as well.
• How to nicely wrap it all up inside an PHP class - or is there such a class already available?

Answer 1

<?php
$date = new DateTime('2000-01-01', new DateTimeZone('Pacific/Nauru'));
echo $date->format('Y-m-d H:i:sP') . "
";

$date->setTimezone(new DateTimeZone('Pacific/Chatham'));
echo $date->format('Y-m-d H:i:sP') . "
";
?>

The above examples will output:

2000-01-01 00:00:00+12:00
2000-01-01 01:45:00+13:45

found on DateTime Manual on php.net

EDIT: Like Pekka said: The DateTime class exists from 5.2 on and there you first have to find out which of the methods are realy implemented and which one only exist from 5.3 on.