lw_test/app/common/model/GradeModel.php

<?php

namespace app\common\model;

class GradeModel extends BaseModel
{
    // 设置表名
    protected $name = 'grade';

    //自动完成
    protected $autoWriteTimestamp = true;

    // 常量
    const IS_FINAL = [1 => '是', 2 => '否'];

    public function getIsFinalTextAttr($value, $data)
    {
        return self::IS_FINAL[$data['is_final']];
    }
}