php计算两个时间差

/** * 计算两个时间差 * @param  [type] $start [description] * @param  [type] $end   [description] * @return [type]        [description] */function cdate($start,$end){    $begin_time = strtotime($start);    $end_time   = strtotime($end);    if($begin_time < $end_time){        $starttime = $begin_time;        $endtime = $end_time;    }else{        $starttime = $end_time;        $endtime = $begin_time;    }    //计算天数    $timediff = $endtime-$starttime;    $days = intval($timediff/86400);    //计算小时数    $remain = $timediff%86400;    $hours = intval($remain/3600);    //计算分钟数    $remain = $remain%3600;    $mins = intval($remain/60);    //计算秒数    $secs = $remain%60;    $res = array("day" => $days,"hour" => $hours,"min" => $mins,"sec" => $secs);    $str=$days."天".$hours."时".$mins."分".$secs."秒";    return $str;    }