IT基地

证件号码加**，用于保密显示使用，可用于多种证件的保密，也可用于手机号等

public function paperEnc($paper_num)
{
    $pm_number = strlen($paper_num); //位数
    switch($pm_number){
        case 7:
            return substr($paper_num,0,2).'***'.substr($paper_num,5);
            break;
        case 8:
            return substr($paper_num,0,3).'***'.substr($paper_num,6);
            break;
        case 15:
            return substr($paper_num,0,10).'*****';
            break;
        case 18:
            return substr($paper_num,0,12).'******';
            break;
        default:
            return '******************';
            break;
    }
}