DESTOON二次开发调用该用户会员注册了多少时间的教程

//会员注册了多少时间统计
function from_date($regtime){
    global $DT_TIME;
    $time = $DT_TIME - $regtime;
    if($time>31536000){
        $year = intval($time/31536000);
        $t = $time%1314000;
        if($t>259200){
            $month = intval($t/259200);
            $x = $t%259200;
            if($x){
                $month += 1;
            }
            return $year.'年'.$month.'个月';
        }else{
            return $year.'年1个月';
        }
    }else{
        if($time>259200){
             $month = intval($time/259200);
             $t = $time%259200;
             if($t>86400){
                 $day = intval($t/86400);
             }else{
                 $day = 1;
             }
             return $month.'个月'.$day.'天';
        }else{
            if($time>86400){
                 $day = intval($t/86400);
             }else{
                 $day = 1;
             }
             return $day.'天';
        }
    }
}