MyBatis在Mapper中传递多个参数的四种方法详解

// Dao层函数
public User getUserByIdAndName(int id, String name);
<!--对应的Mapper中-->
<select id="getUserByIdAndName" resultType="User">
  SELECT * FROM user WHERE id = #{0} AND name = #{1}
</select>

// Dao层函数
public User getUserByIdAndName(@Param("id") int id, @Param("name") String name);
<!-- 对应的Mapper中 -->
<select id="getUserByIdAndName" resultType="User">
  SELECT * FROM user WHERE id = #{id} AND name = #{name}
</select>

// Dao层函数
public User getUser(Map<String, Object> map);
<!-- 对应的Mapper中 -->
<select id="getUser" resultType="User">
  SELECT * FROM user WHERE id = #{id} AND name = #{name}
</select>

Map<String, Object> map = new HashMap<>();
map.put("id", 1);
map.put("name", "张三");
User user = userDao.getUser(map);

public class User {
    private int id;
    private String name;
    private int age;
    // 省略getter和setter方法
}

public User getUser(User user);

<select id="getUser" resultType="com.example.User">
  SELECT * FROM user WHERE id = #{id} AND name = #{name} AND age = #{age}
</select>

User user = new User();
user.setId(1);
user.setName("张三");
user.setAge(20);
User result = userDao.getUser(user);

SELECT * FROM user WHERE id = 1 AND name = '张三' AND age = 20