PHP Manual: Set the day on which the week is deemed to start

Description

Object-oriented style

public true IntlCalendar::setFirstDayOfWeek(int $dayOfWeek)

Procedural style

true intlcal_set_first_day_of_week(IntlCalendar $calendar, int $dayOfWeek)

Defines the day of week deemed to start the week. This affects the behavior of fields that depend on the concept of week start and end such as IntlCalendar::FIELD_WEEK_OF_YEAR and IntlCalendar::FIELD_YEAR_WOY.

Parameters

calendar: An IntlCalendar instance.
dayOfWeek: One of the constants IntlCalendar::DOW_SUNDAY, IntlCalendar::DOW_MONDAY, …, IntlCalendar::DOW_SATURDAY.

Return Values

Always returns true.

Changelog

Version	Description
8.2.0	The return type is `true` now; previously, it was bool.

Examples

Example #1 IntlCalendar::setFirstDayOfWeek

<?php
ini_set('date.timezone', 'Europe/Lisbon');
ini_set('intl.default_locale', 'es_ES');

$cal = IntlCalendar::createInstance();
$cal->set(2013, 5 /* June */, 30); // A Sunday

var_dump($cal->getFirstDayOfWeek()); // 2 (Monday)

echo IntlDateFormatter::formatObject($cal, <<<EOD
'local day of week: 'cc'
week of month    : 'W'
week of year     : 'ww
EOD
), "\n";

$cal->setFirstDayOfWeek(IntlCalendar::DOW_SUNDAY);

echo IntlDateFormatter::formatObject($cal, <<<EOD
'local day of week: 'cc'
week of month    : 'W'
week of year     : 'ww
EOD
), "\n";

The above example will output:

int(2)
local day of week: 7
week of month    : 4
week of year     : 26
local day of week: 1
week of month    : 5
week of year     : 27