Think视图模型格式

<?php
namespace Admin\ViewModel;
use Think\Model\ViewModel;
Class FreezerViewModel extends ViewModel{
protected $connection = 'haoexian1103'; //连接数据库
protected $viewFields = array(
't_api_freezer'=>array('id','device_name','device_num','type','capacity','status','lng','lat'),
't_sys_region'=>array('name','address','parent_id','status'=>'regionstatus','remark','_on' => 't_api_freezer.region_id = t_sys_region.id')
);
}