In response to the other comments expressing surprise that changing the timezone does not affect the timestamp:
A UNIX timestamp is defined as the number of seconds that have elapsed since 00:00:00 (UTC), Thursday, 1 January 1970.
So: with respect to UTC. Always.
Calling setTimezone() never changes the actual "absolute", underlying, moment-in-time itself. It only changes the timezone you wish to "view" that moment "from". Consider the following:
<?php
// A time in London.
$datetime = new DateTime('2015-06-22T10:40:25', new DateTimeZone('Europe/London'));
// I wonder how that SAME moment-in-time would
// be described in other places around the world.
$datetime->setTimezone(new DateTimeZone('Australia/Sydney'));
print $datetime->format('Y-m-d H:i:s (e)');
// 2015-06-22 19:40:25 (Australia/Sydney)
$datetime->setTimezone(new DateTimeZone('America/New_York'));
print $datetime->format('Y-m-d H:i:s (e)');
// 2015-06-22 05:40:25 (America/New_York)
$datetime->setTimezone(new DateTimeZone('Asia/Calcutta'));
print $datetime->format('Y-m-d H:i:s (e)');
// 2015-06-22 15:10:25 (Asia/Calcutta)
?>
Please note that ALL of these date strings unambiguously represent the exact same moment-in-time. Therefore, calling getTimestamp() at any stage will return the same result:
<?php
$datetime->getTimestamp();
// 1434966025
?>
DateTime::setTimezone
date_timezone_set
(PHP 5 >= 5.2.0, PHP 7, PHP 8)
DateTime::setTimezone -- date_timezone_set — Legt die Zeitzone für ein DateTime-Objekt fest
Beschreibung
Objektorientierter Stil
Prozeduraler Stil
Legt eine neue Zeitzone für ein DateTime-Objekt fest.
Wie DateTimeImmutable::setTimezone(), verwendet aber DateTime.
Die prozedurale Version verwendet das DateTime-Objekt als ersten Parameter.
Parameter-Liste
-
object -
Nur bei prozeduralem Aufruf: Ein von date_create() zurückgegebenes DateTime-Objekt. Diese Funktion verändert dieses Objekt.
-
timezone -
Ein DateTimeZone-Objekt, das die gewünschte Zeitzone repräsentiert.
Rückgabewerte
Gibt das DateTime-Objekt für die Methodenverkettung zurück. Der zugrunde liegende Zeitpunkt wird beim Aufruf dieser Methode nicht verändert.
Beispiele
Beispiel #1 DateTime::setTimeZone()-Beispiel
Objektorientierter Stil
<?php
$date = new DateTime('2000-01-01', new DateTimeZone('Pacific/Nauru'));
echo $date->format('Y-m-d H:i:sP') . "\n";
$date->setTimezone(new DateTimeZone('Pacific/Chatham'));
echo $date->format('Y-m-d H:i:sP') . "\n";
?>Prozeduraler Stil
<?php
$date = date_create('2000-01-01', timezone_open('Pacific/Nauru'));
echo date_format($date, 'Y-m-d H:i:sP') . "\n";
date_timezone_set($date, timezone_open('Pacific/Chatham'));
echo date_format($date, 'Y-m-d H:i:sP') . "\n";
?>Die obigen Bespiele erzeugen folgende Ausgabe:
2000-01-01 00:00:00+12:00 2000-01-01 01:45:00+13:45
Siehe auch
- DateTimeImmutable::setTimezone() - Legt die Zeitzone fest
- DateTime::getTimezone() - Liefert die Zeitzone relativ zur angegebenen DateTime
- DateTimeZone::__construct() - Erstellt neues DateTimeZone-Objekt
add a note
User Contributed Notes 6 notes
jamsilver at gmail dot com ¶
9 years ago
Alex ¶
8 years ago
Surprising that the timezone works only specified in the separated method in case if you'll use ->format('U').
this does NOT apply timezone +0200 in the $timestamp:
<?php
$date = new \DateTime(strtotime(time()), new DateTimeZone(system('date +%z')));
$timestamp = $date->format('U');
?>
this will apply timezone +0200 in the $timestamp:
<?php
$date = new \DateTime(strtotime(time()));
$date->setTimezone(new DateTimeZone(system('date +%z')));
$timestamp = $date->format('U');
?>
keithm at aoeex dot com ¶
14 years ago
The timestamp value represented by the DateTime object is not modified when you set the timezone using this method. Only the timezone, and thus the resulting display formatting, is affected.
This can be seen using the following test code:
<?php
$MNTTZ = new DateTimeZone('America/Denver');
$ESTTZ = new DateTimeZone('America/New_York');
$dt = new DateTime('11/24/2009 2:00 pm', $MNTTZ);
var_dump($dt->format(DATE_RFC822), $dt->format('U'));
$dt->setTimezone($ESTTZ);
var_dump($dt->format(DATE_RFC822), $dt->format('U'));
/** Output:
string(29) "Tue, 24 Nov 09 14:00:00 -0700"
string(10) "1259096400"
string(29) "Tue, 24 Nov 09 16:00:00 -0500"
string(10) "1259096400"
**/
?>
As such, you can use this to easily convert between timezones for display purposes.
forzi at mail333 dot com ¶
10 years ago
<?php
$MNTTZ = new DateTimeZone('America/Denver');
$ESTTZ = new DateTimeZone('America/New_York');
$dt = new DateTime('11/24/2009 2:00 pm', $MNTTZ);
var_dump($dt->format(DATE_RFC822), $dt->format('U'));
$dt->setTimezone($ESTTZ);
var_dump($dt->format(DATE_RFC822), $dt->format('U'));
?>
doesn't changes timestamp
But
<?php
$MNTTZ = new DateTimeZone('America/Denver');
$ESTTZ = new DateTimeZone('-0500');
$dt = new DateTime('11/24/2009 2:00 pm', $MNTTZ);
var_dump($dt->format(DATE_RFC822), $dt->format('U'));
$dt->setTimezone($ESTTZ);
var_dump($dt->format(DATE_RFC822), $dt->format('U'));
?>
changes timestamp
It is possible to fix that by:
<?php
$timestamp = $date->getTimestamp();
$date->setTimezone($value);
$date->setTimestamp($timestamp);
?>
But WTF???
balbuf ¶
8 years ago
It appears that what forzi at mail333 dot com said is correct.
When you reset the timezone on a DateTime object using a timezone that was instantiated with a GMT offset (e.g. <?php new DateTimeZone('-0500'); ?>) the timestamp as reported by <?php $dt->format('U'); ?> changes.
However, the value reported by <?php $dt->getTimestamp(); ?> does _not_ change. Interestingly, once <?php $dt->getTimestamp(); is called, the value from <?php $dt->format('U'); ?> starts returning the correct timestamp. This appears to be a bug.
In any case, other output values from format() seem to be accurate, and the true timestamp is always accessible via getTimestamp().
salladin ¶
12 years ago
I found unexpected behaviour when passing a timestamp.
timezone seems to always be GMT+0000 unless setTimezone() is set.
<?php
$MNTTZ = new DateTimeZone('America/Denver');
$ts = 1336476757;
$dt = new DateTime("@$ts", $MNTTZ);
var_dump($dt->format('T'), $dt->format('U'));
$dt->setTimezone($MNTTZ);
var_dump($dt->format('T'), $dt->format('U'));
/** Output:
string(8) "GMT+0000"
string(10) "1336476757"
string(3) "MDT"
string(10) "1336476757"
**/
?>
