PHP Manual: Returns all transitions for the timezone

Description

Object-oriented style

public arrayfalse DateTimeZone::getTransitions(int $timestampBegin = PHP_INT_MIN, int $timestampEnd = PHP_INT_MAX)

Procedural style

arrayfalse timezone_transitions_get(DateTimeZone $object, int $timestampBegin = PHP_INT_MIN, int $timestampEnd = PHP_INT_MAX)

Parameters

object: Procedural style only: A DateTimeZone object returned by timezone_open
timestampBegin: Begin timestamp.
timestampEnd: End timestamp.

Return Values

Returns a numerically indexed array of transition arrays on success, or false on failure. DateTimeZone objects wrapping type 1 (UTC offsets) and type 2 (abbreviations) do not contain any transitions, and calling this method on them will return false.

If timestampBegin is given, the first entry in the returned array will contain a transition element at the time of timestampBegin.

**Transition Array Structure**
Key	Type	Description
`ts`	int	Unix timestamp
`time`	string	`DateTimeInterface::ISO8601_EXPANDED` (PHP 8.2 and later), or `DateTimeInterface::ISO8601` (PHP 8.1 and lower) time string
`offset`	int	Offset to UTC in seconds
`isdst`	bool	Whether daylight saving time is active
`abbr`	string	Timezone abbreviation

Examples

Example #1 A timezone_transitions_get example

<?php
$timezone = new DateTimeZone("Europe/London");
$transitions = $timezone->getTransitions();
print_r(array_slice($transitions, 0, 3));
?>

The above example will output something similar to:

Array
(
    [0] => Array
        (
            [ts] => -9223372036854775808
            [time] => -292277022657-01-27T08:29:52+0000
            [offset] => 3600
            [isdst] => 1
            [abbr] => BST
        )

    [1] => Array
        (
            [ts] => -1691964000
            [time] => 1916-05-21T02:00:00+0000
            [offset] => 3600
            [isdst] => 1
            [abbr] => BST
        )

    [2] => Array
        (
            [ts] => -1680472800
            [time] => 1916-10-01T02:00:00+0000
            [offset] => 0
            [isdst] => 
            [abbr] => GMT
        )

)

Example #2 A timezone_transitions_get example with timestampBegin set

<?php
$timezone = new DateTimeZone("Europe/London");
$transitions = $timezone->getTransitions(time());
print_r(array_slice($transitions, 0, 3));
?>

The above example will output something similar to:

Array
(
    [0] => Array
        (
            [ts] => 1654184161
            [time] => 2022-06-02T15:36:01+0000
            [offset] => 3600
            [isdst] => 1
            [abbr] => BST
        )

    [1] => Array
        (
            [ts] => 1667091600
            [time] => 2022-10-30T01:00:00+0000
            [offset] => 0
            [isdst] => 
            [abbr] => GMT
        )

    [2] => Array
        (
            [ts] => 1679792400
            [time] => 2023-03-26T01:00:00+0000
            [offset] => 3600
            [isdst] => 1
            [abbr] => BST
        )

)