mybatis的#{}传递字符类型参数没有结果,${}有结果,为什么?

Question

我使用idea编写javaweb时在mybatis用#{}传String类型的参数返回结果为空,但我用${}传参返回就有结果.

sql语句编写部分:

    <select id="selectById" resultMap="brandResultMap">
        select *
        from stu
        where name
        like #{name};
    </select>

test代码部分:

    @Test
    public void testSelectById() throws IOException {
        //接收参数
        String name = "马运";
        name="'"+name+"'";
        //int id = 3;
        //int math = 222;
        //int english = 77;
        Map map = new HashMap();
        map.put("name" , name);
        //map.put("english" , english);
        //1. 获取SqlSessionFactory
        String resource = "mybatis-config.xml";
        InputStream inputStream = Resources.getResourceAsStream(resource);
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        //2. 获取SqlSession对象
        SqlSession sqlSession = sqlSessionFactory.openSession();
        //3. 获取Mapper接口的代理对象
        BrandMapper brandMapper = sqlSession.getMapper(BrandMapper.class);
        //4. 执行方法
        List<Brand> brand = brandMapper.selectById(map);
        //Brand brand = brandMapper.selectById(id);
        System.out.println(brand);
        //5. 释放资源
        sqlSession.close();
    }

结果:

当我把xml里编写sql语句的传参方法#{}改为${},其余都不变运行就有结果

#{}传递int类型写成的sql语句查询有返回结果,为什么我用#{}传递String类型的参数就不行呢?

Answer 1

没有%