一共介绍三种方式
第一种方式
用#{0}表示第一个参数、#{1}表示第二参数…以此类推
service
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| public User findByMutiParam(String name, String password) {
return userDao.findByMutiParam(name, password);
}
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dao
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| User findByMutiParam(String name, String password);
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xml
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| <select id="findByMutiParam" resultType="com.mybatis.entity.User">
SELECT
*
FROM
user
WHERE
name = #{0} and password = #{1}
</select>
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第二种方式
参数封装map集合
service
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| public User findByMap(String name, String password) {
Map<String, Object> map = new HashMap<String, Object>();
map.put("name", name);
map.put("password", password);
return userDao.findByMap(map);
}
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dao
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| User findByMap(Map<String, Object> map);
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xml
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| <select id="findByMap" resultType="com.mybatis.entity.User">
SELECT
*
FROM
user
WHERE
name = #{name} and password = #{password}
</select>
|
第三种方式
使用注解（推荐）参数清晰明了
service
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| public User findByAnnotation(String name, String password) {
return userDao.findByAnnotation(name, password);
}
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dao
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| User findByAnnotation(@Param("name") String name, @Param("password") String password);
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xml
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| <select id="findByAnnotation" resultType="com.mybatis.entity.User">
SELECT
*
FROM
user
WHERE
name = #{name} and password = #{password}
</select>
|