MyBatis入参方式

public  void  deletePerson(Integer id);  //接口

<!-- mapper配置文件-->
  <delete id="deletePerson" parameterType="int">

      delete from person where id=#{parameter1} <!-- #{}里面写任何值都能取到值-->
    
  </delete>

public Person getPersonByNameAndGender(Map<String,Object> param);//接口

  <select id="getPersonByNameAndGender" resultType="person">

    select * from person where username=#{username} and gender=#{gender}
    
    <!--#{}里面填写Map的key值-->
  </select>

//将要传递的参数封装在一个对象中
public Person getPersonByNameAndGender(Person person);

  <select id="getPersonByNameAndGender" resultType="person">

    select * from person where username=#{username} and gender=#{gender}

    <!--#{}里填写person对象里面的属性-->
  </select>

public Person getPersonByNameAndGender(@Param("username") String username, @Param("gender") String gender);

  <select id="getPersonByNameAndGender" resultType="person">

    select * from person where username=#{username} and gender=#{gender}

  </select>

 public Person getPersonByCollection(@Param("test") int[] ids);

<select id="getPersonByCollection" resultType="person">

    select * from person where id=#{test[0]}
  </select>

public List<Person> getPersonsByIds(@Param("test")int[] ids);

  <select id="getPersonsByIds" resultType="person">

    select * from person where id in

    <foreach collection="test" item="id" index="i" open="(" close=")" separator=",">
      #{id}
    </foreach>

<!--collection表示选取的集合，item表示当前遍历的对象，index表示当前遍历的索引-->
<!--若test这个数组里面为test[]{1,2,3},则上面的sql语句相当于select * from person id in (1,2,3,4)-->
  </select>