根据区域设置查找第一天和上周的日期

Question

我试图根据语言环境找到第一天和最后一周的日子.在周日的美国周开始,但在其他国家,它可能在星期一甚至星期六开始.

setlocale(LC_ALL, "en_US.UTF-8");
date_default_timezone_set("America/New_York");

$start_week = (new DateTimeImmutable());
$start_week = $start_week->modify('this week');
$end_week = $start_week->modify('this week +6 days');

$interval = new DateInterval('P1D');
$week_range = new DatePeriod($start_week, $interval, $end_week);

foreach($week_range as $week_day) {
  // $week_day starts with Monday, supposed to be Sunday
}

Answer 1

一种方法是使用IntlCalendar类.它有一个方法getFirstDayofWeek() ,它返回一个整数,对应于DOW_在常量IntlCalendar:

const integer DOW_SUNDAY = 1 ;
const integer DOW_MONDAY = 2 ;
const integer DOW_TUESDAY = 3 ;
const integer DOW_WEDNESDAY = 4 ;
const integer DOW_THURSDAY = 5 ;
const integer DOW_FRIDAY = 6 ;
const integer DOW_SATURDAY = 7 ;

使用它可以在呼叫开始日时将天数添加到DateTimeImmutable::modify()开始日期.在这个phpfiddle中看到它有三个区域设置(即en_US,es_ES,sw_KE).

$locale = 'es_ES'; //Spain Spanish locale
$cal1 = IntlCalendar::createInstance(NULL, $locale);
$firstDayOfWeek = $cal1->getFirstDayOfWeek();
$daysToAdd = $firstDayOfWeek - 2; //difference from US M-Sunday 
echo 'locale: '.$local.' first day of week: '.$cal1->getFirstDayOfWeek().' days to add: '.$daysToAdd.'<br />';
$start_week = new DateTimeImmutable();
$start_week = $start_week->modify('this week +'.$daysToAdd.' days');
$end_week = $start_week->modify('+6 days');
$interval = new DateInterval('P1D');
$week_range = new DatePeriod($start_week, $interval, $end_week);

foreach($week_range as $week_day) {
    echo 'week day: '.$week_day->format('l m/d/Y').'<br />';
}