Question

Am trying to get the time difference between two days. But for certain date/time, I get wrong answers

Here is my code:

/****************************************
$start_date = new DateTime('23:58:40'); *These two still give 
$end_date = new DateTime('00:00:00');   *a wrong answer
*****************************************/

$start_date = new DateTime('23:58:40');
$end_date = new DateTime('00:11:36');

$dd = date_diff($end_date, $start_date);

//Giving a wrong answer: Hours = 23, Minutes = 47, Seconds = 4 
echo "Hours = $dd->h, Minutes = $dd->i, Seconds = $dd->s";

Answer 1

The awnser is correct. You provide two times. Without a date there is no way to know the last date is actually the next day. Just because you named the variable “end_date” doesnt mean PHP knows what you mean.

Perhaps you should include the date aswell in your request like

$start_date = new DateTime('2012-12-07 23:58:40');
$end_date = new DateTime('2012-12-08 00:11:36');

If you realy want to work with just times:

function differenceInTimes($start, $end) {
    if (strtotime($start)>strtotime($end)) {
        //start date is later then end date
        //end date is next day
        $s = new DateTime('2000-01-01 '.$start);
        $e = new DateTime('2000-01-02 '.$end);
    } else {
        //start date is earlier then end date
        //same day
        $s = new DateTime('2000-01-01 '.$start);
        $e = new DateTime('2000-01-01 '.$end);
    }

    return date_diff($s, $e);
}

$start_date = '23:58:40';
$end_date = '00:11:36';
$dd = differenceInTimes($start_date, $end_date);
echo "Hours = $dd->h, Minutes = $dd->i, Seconds = $dd->s";

//Hours = 0, Minutes = 12, Seconds = 56