The IntlCalendar::getFirstDayOfWeek() function is an inbuilt function in PHP which is used to return the first day of the week for the calendar.
Syntax:
- Object oriented style
int IntlCalendar::getFirstDayOfWeek( void )
- Procedural style
int intlcal_get_first_day_of_week( IntlCalendar $cal )
Parameters: This function uses single parameter $cal which holds the resource of IntlCalendar.
Return Value: This function returns one of the IntlCalendar field constants like IntlCalendar::DOW_SUNDAY, IntlCalendar::DOW_MONDAY, …, IntlCalendar::DOW_SATURDAY on success or FALSE on failure.
Below program illustrates the IntlCalendar::getFirstDayOfWeek() function in PHP:
Program:
<?php   // Set the DateTime zone ini_set('date.timezone', 'Asia/Calcutta'); ini_set('date.timezone', 'UTC');   // Set the DateTime object $calendar1 = IntlCalendar::fromDateTime('2019-09-22');   // Use getFirstDayOfWeek() function to get // the first day of week var_dump($calendar1->getFirstDayOfWeek());   // Get the week of year var_dump($calendar1->get(IntlCalendar::FIELD_WEEK_OF_YEAR));   // Create an instance of calendar $calendar2 = IntlCalendar::createInstance(NULL, 'en_US');   // Use getFirstDayOfWeek() function to get // the first day of week var_dump($calendar2->getFirstDayOfWeek());   // Set the date to the calendar $calendar2->set(2020, 05, 20);   // Check the given month is leap or not var_dump($calendar2->get(IntlCalendar::FIELD_IS_LEAP_MONTH));   ?> |
Output:
int(1) int(39) int(1) int(0)
Reference: https://www.php.net/manual/en/intlcalendar.getfirstdayofweek.php
