仅使用strtotime，本月第一天凌晨0点使用PHP？

Question

echo mydate(strtotime('1 am first day of this month'));

Above works with result 2017-10-01 01:00:00 , but I have difficulty to do it for 0 am. Neither 24am, 24pm, 0pm, first second works.

Answer 1

Use midnight :

echo mydate(strtotime('midnight first day of this month'));

Demo

Answer 2

Better to use DateTime for date and time manipulations,

$date = new DateTime('midnight first day of this month'); echo $date->format('Ymd H:i:s');

or if there is need to UnixTimestamp : $date->format('U'); or echo $date->getTimestamp();