84
votes

So I've checked the list of supported time zones in PHP and I was wondering how could I include them in the date() function? Thanks!

I don't want a default timezone, each user has their timezone stored in the database, I take that timezone of the user and use it. How? I know how to take it from the database, not how to use it, though.

11
In which format you store time zones? - revo

11 Answers

147
votes

For such task, you should really be using PHP's DateTime class. Please ignore all of the answers advising you to use date() or date_set_time_zone, it's simply bad and outdated.

I'll use pseudocode to demonstrate, so try to adjust the code to suit your needs.

Assuming that variable $tz contains string name of a valid time zone and variable $timestamp contains the timestamp you wish to format according to time zone, the code would look like this:

$tz = 'Europe/London';
$timestamp = time();
$dt = new DateTime("now", new DateTimeZone($tz)); //first argument "must" be a string
$dt->setTimestamp($timestamp); //adjust the object to correct timestamp
echo $dt->format('d.m.Y, H:i:s');

DateTime class is powerful, and to grasp all of its capabilities - you should devote some of your time reading about it at php.net. To answer your question fully - yes, you can adjust the time zone parameter dynamically (on each iteration while reading from db, you can create a new DateTimeZone() object).

39
votes

If I understood correct,You need to set time zone first like:

date_default_timezone_set('UTC');

And than you can use date function:

// Prints something like: Monday 8th of August 2005 03:12:46 PM
echo date('l jS \of F Y h:i:s A');
18
votes

Use the DateTime class instead, as it supports timezones. The DateTime equivalent of date() is DateTime::format.

An extremely helpful wrapper for DateTime is Carbon - definitely give it a look.

You'll want to store in the database as UTC and convert on the application level.

13
votes

The answer above caused me to jump through some hoops/gotchas, so just posting the cleaner code that worked for me:

$dt = new DateTime();
$dt->setTimezone(new DateTimeZone('America/New_York'));
$dt->setTimestamp(123456789);

echo $dt->format('F j, Y @ G:i');
11
votes

It should like this:

date_default_timezone_set('America/New_York');
5
votes

U can just add, timezone difference to unix timestamp. Example for Moscow (UTC+3)

echo date('d.m.Y H:i:s', time() + 3 * 60 * 60);
4
votes

this works perfectly in 2019:

date('Y-m-d H:i:s',strtotime($date. ' '.$timezone)); 
2
votes

Try this. You can pass either unix timestamp, or datetime string

public static function convertToTimezone($timestamp, $fromTimezone, $toTimezone, $format='Y-m-d H:i:s') 
    {
        $datetime = is_numeric($timestamp) ?
                    DateTime::createFromFormat ('U' , $timestamp, new DateTimeZone($fromTimezone)) :
                    new DateTime($timestamp, new DateTimeZone($fromTimezone));

        $datetime->setTimezone(new DateTimeZone($toTimezone));

        return $datetime->format($format);
    }
2
votes

I have created this very straightforward function, and it works like a charm:

function ts2time($timestamp,$timezone){ /* input: 1518404518,America/Los_Angeles */            
        $date = new DateTime(date("d F Y H:i:s",$timestamp));
        $date->setTimezone(new DateTimeZone($timezone));
        $rt=$date->format('M d, Y h:i:s a'); /* output: Feb 11, 2018 7:01:58 pm */
        return $rt;
    }
1
votes

Not mentioned above. You could also crate a DateTime object by providing a timestamp as string in the constructor with a leading @ sign.

$dt = new DateTime('@123456789');
$dt->setTimezone(new DateTimeZone('America/New_York'));
echo $dt->format('F j, Y - G:i');

See the documentation about compound formats: https://www.php.net/manual/en/datetime.formats.compound.php

-2
votes

You can replace database value in date_default_timezone_set function, date_default_timezone_set(SOME_PHP_VARIABLE); but just needs to take care of exact values relevant to the timezones.