PHP Add Up Hours, Minutes, Seconds

Question

Given a series of hours, minutes, and seconds (ex: 01:30:00 or 00:30:00), I would like to add up each and convert the sum to seconds.

For example, if the total time

Answer 1

$timestr = '00:30:00';

$parts = explode(':', $timestr);

$seconds = ($parts[0] * 60 * 60) + ($parts[1] * 60) + $parts[2];