php月份按周分段，以及判断当前时间是当月的第几周

date.php

<?php
class Date {
//月转化为周
    private function month2Week(int $year, int $month): array
    {
        $start = 1;
        $end = date('d', strtotime(date("{$year}-{$month}-01") . ' + 1 month - 1 day'));
        $days = range($start, $end);
        return array_chunk($days, 7);
    }

    //时间戳判断当前是第几周
    private function whichWeek(int $timeStamp): int
    {
        $date = date('Y-m-d', $timeStamp);
        list($year, $month, $day) = explode('-', $date);

        $weeks = $this->month2Week($year, $month);
        foreach ($weeks as $key => $weekDays) {
            if (in_array($day, $weekDays)) {
                return $key + 1;
            }
        }
        return 0;

    }
}