PHP 日時アプリケーション 13: 2 つの日付の間の週数を計算する

<?php
function week_between_two_dates($date1, $date2)
{
    $first = DateTime::createFromFormat(&#39;m/d/Y&#39;, $date1);
    $second = DateTime::createFromFormat(&#39;m/d/Y&#39;, $date2);
    if($date1 > $date2) return week_between_two_dates($date2, $date1);
    return floor($first->diff($second)->days/7);
}

$dt1 = &#39;1/1/2020&#39;;
$dt2 = &#39;12/29/2020&#39;;
echo $dt1.&#39; 和 &#39;. $dt2. &#39; 之间相差的周数是 &#39;. week_between_two_dates($dt1, $dt2)." 周 ";

1/1/2020 和 12/29/2020 之间相差的周数是 51 周

public static DateTime::createFromFormat(string $format, string $time, DateTimeZone $timezone = ?): DateTime

date_create_from_format(string $format, string $time, DateTimeZone $timezone = ?): DateTime