Yii2 PHP从日期开始获取一周中的第一天和一个月的最后一天

我假设您有$date\u submit值,并且希望在$week\u submit和$month\u submit中获得新的所需值。尝试以下操作:

$date='2017-12-18';//$_POST['date_submit'];//date('Y-m-d');//'2017-12-19';
$day = DateTime::createFromFormat('Y-m-d', $date);
$day->setISODate((int)$day->format('o'), (int)$day->format('W'), 1);
$week_submit = $day->format('Y-m-d');

$month_submit=date("Y-m-t", strtotime($date));

print_r ('Week submit: '.$week_submit.'<br>'.'Month submit: '.$month_submit);