<?php

// We'll start by getting the current time.
$now = new DateTime();
echo $now->format('Y-m-d H:i:s.u P T') . "\n";

// You can create a DateTime object by providing the 
// year, month, day, etc. Times are always associated
// with a timezone.
$then = new DateTime('2009-11-17 20:34:58.651387', new DateTimeZone('UTC'));
echo $then->format('Y-m-d H:i:s.u P T') . "\n";

// You can extract the various components of the time
// value as expected.
echo $then->format('Y') . "\n";
echo $then->format('F') . "\n";
echo $then->format('d') . "\n";
echo $then->format('H') . "\n";
echo $then->format('i') . "\n";
echo $then->format('s') . "\n";
echo $then->format('u') . "\n";
echo $then->getTimezone()->getName() . "\n";

// The day of the week is also available.
echo $then->format('l') . "\n";

// These methods compare two times, testing if the
// first occurs before, after, or at the same time
// as the second, respectively.
echo ($then < $now ? 'true' : 'false') . "\n";
echo ($then > $now ? 'true' : 'false') . "\n";
echo ($then == $now ? 'true' : 'false') . "\n";

// The diff method returns a DateInterval object representing
// the interval between two times.
$diff = $now->diff($then);
echo $diff->format('%R%y years, %m months, %d days, %H hours, %i minutes, %s seconds') . "\n";

// We can compute the length of the duration in
// various units.
echo $diff->days * 24 + $diff->h . "\n";
echo $diff->days * 24 * 60 + $diff->h * 60 + $diff->i . "\n";
echo $diff->days * 24 * 60 * 60 + $diff->h * 60 * 60 + $diff->i * 60 + $diff->s . "\n";

// You can use add and sub to advance a time by a given
// interval, or move backwards by an interval.
$interval = new DateInterval('P10Y10M10DT10H10M10S');
echo $then->add($interval)->format('Y-m-d H:i:s.u P T') . "\n";
echo $then->sub($interval)->format('Y-m-d H:i:s.u P T') . "\n";

?>