PHP | timezone_identifiers_list() Function

The timezone_identifiers_list() function is an inbuilt function in PHP which is used to return an indexed array containing all the timezone identifiers. The datetimezone object is sent as a parameter to the timezone_identifiers_list() function and it returns an indexed array on success or False on failure.

Syntax:

array timezone_identifiers_list( $datetimezone, $country )

Parameters: This function accepts two parameter as mentioned above and described below:

• $datetimezone: It is an optional parameter which specifies the DateTimeZone class constant.
• country: It is also an optional parameter which specifies a two-letter ISO 3166-1 compatible country code.

Return Value: This function returns an indexed array on success or False on failure.

Exceptions: The timezone_identifiers_list() function is an alias of DateTimeZone::listIdentifiers() function.

Below programs illustrate the timezone_identifiers_list() function in PHP:

Program 1:

<?php

// Displaying all the timezone identifiers of Antarctica
echo ("All the timezones available in this timezone are ");
print_r(timezone_identifiers_list(4));
?>

Output:

All the timezones available in this timezone are Array
(
    [0] => Antarctica/Casey
    [1] => Antarctica/Davis
    [2] => Antarctica/DumontDUrville
    [3] => Antarctica/Macquarie
    [4] => Antarctica/Mawson
    [5] => Antarctica/McMurdo
    [6] => Antarctica/Palmer
    [7] => Antarctica/Rothera
    [8] => Antarctica/Syowa
    [9] => Antarctica/Troll
    [10] => Antarctica/Vostok
)

Program 2:

<?php

// Displaying the timezone identifiers of Africa
$timezone_identifiers = DateTimeZone::listIdentifiers();
for ($i = 0; $i < 8; $i++)
{
    echo "$timezone_identifiers[$i]\n";
}
?>

Output:

Africa/Abidjan
Africa/Accra
Africa/Addis_Ababa
Africa/Algiers
Africa/Asmara
Africa/Bamako
Africa/Bangui
Africa/Banjul

Reference: http://php.net/manual/en/function.timezone-identifiers-list.php