PHP time comparison function, returns the seconds, minutes, hours or days between two dates

function DateDiff($date1, $date2, $unit = "") { //Time comparison function, returns the number of seconds, minutes, hours or days between two dates
 switch ($unit) {
 case 's':
 $dividend = 1;
 break;
 case 'i':
 $dividend = 60; //oSPHP.COM.CN
 break;
 case 'h':
 $dividend = 3600;
 break ;
 case 'd':
 $dividend = 86400;
 break; //Open source OSPhP.COM.CN
 default:
 $dividend = 86400;
 }
 $time1 = strtotime($date1);
 $time2 = strtotime ($date2);
 if ($time1 && $time2)
 return (float)($time1 - $time2) / $dividend;
 return false;
}

Days, minutes, seconds