PHP calc difference between time greater than 24 hours

Question

What is the best way to calculate the difference in time, when time is greater than 24 hours.

Example

$time1 = \'76:00:00\';
$time2          


        

Answer 1

Use \DateTime and \DateInterval to perform calculations:

$date1 = new \DateTime('now', new DateTimeZone('UTC'));
$date2 = new \DateTime('now', new DateTimeZone('UTC'));
$time1 = new \DateInterval('PT76H');
$time2 = new \DateInterval('PT30H');

$date1->add($time1);
$date2->add($time2);

$diff = $date1->diff($date2);
echo ($diff->days * 24 + $diff->h) . $diff->format(':%I:%S');

Explanation: It's not possible to perform calculations directly on DateIntervals, so you have to create dates as a basis for calculations. Then add two different intervals to current dates, and calculate a difference between them. diff() returns \DateInterval that contains total number of days, that you have to multiply by 24 to get hours, and hours that don't make full days.

EDIT: The timezone should be specified as UTC to avoid daylight saving time issues.