project/app/admin/model/City.php

<?php
namespace app\admin\model;

class City extends Base
{
//设置字段信息
    protected $schema = [
        'id'       =>'int',//
        'name'       =>'varchar',//市名
        'city_code'       =>'varchar',//市级code
        'province_code'       =>'varchar',//省级code

    ];
}