如何在PHP中将日期变量和时间变量转换为一个时间戳变量？

I have a variable (startsAt) that is a date variable, and I have a variable (startsTime) that is a time variable. I would like to combine those two variables into a timestamp and use that timestamp to update a database in SQL. Can anybody help with this?

HI you can just concatenate the two and

   $timestamp = strtotime( $startAt . ' ' . $startTime );

assuming both are in valid date formats. such as 'Y-m-d H:i:s', for example you have a date Y-m-d and a time H:i:s, or in english 2016-06-15 and 17:25:00

php.net/manual/en/function.strtotime.php