PHP Date difference
Try like
$dStart = strtotime('2013-03-15');$dEnd = strtotime('2013-04-01');$dDiff = $dEnd - $dStart;echo date('H:i:s',$dDiff);
or as per your code try with
$dDiff = $dStart->diff($dEnd);$date->format('d',$dDiff);echo $dDiff->days;
if you want diff in days try with this also
echo floor($dDiff/(60*60*24));