cxinv/app/admin/model/SupplierInfo.php

<?php
declare (strict_types = 1);

namespace app\admin\model;

use think\Model;

/**
 * @mixin \think\Model
 */
class SupplierInfo extends Model
{
    public static function getRegisterCode($code){
        return SupplierInfo::where(['code'=>$code])->value("registercode","");
    }
}