Mybatis框架中，Mapper檔案引數獲取一般有以下幾種：

1、引數個數為1個（string或者int）

dao層方法為以下兩種：

  /**

     * 單個int型

     */

        public List<UserComment> findByDepartmentId(int dapartmentId);

     

    /**

     * 單個string型

     */

     public Source findByTitle(String title);

對應的Mapper取值：

取值時應當注意，引數名字應該與dao層傳入的引數名字相同。

  /*單個int型*/

    <select id="findByDepartmentId"  resultType="com.bonc.wechat.entity.publicserver.UserComment">

     select * from wx_user_comment where

     department_id=#{departmentId}

     order by createtime desc;

    </select>

     

     

    /*單個string型*/

    <select id="findByTitle"  parameterType="java.lang.String" resultType="com.bonc.wechat.entity.publicserver.Source">

     select * from wx_source where

            title=#{title};

    </select>
 

    或者直接使用通用方法獲取引數

     

    <select id="findByDepartmentId"  resultType="com.bonc.wechat.entity.publicserver.UserComment">

     select * from wx_user_comment where

     department_id=#{_parameter}

     order by createtime desc;

    </select>

     

     

     

    <select id="findByTitle"  parameterType="java.lang.String" resultType="com.bonc.wechat.entity.publicserver.Source">

     select * from wx_source where

            title=#{_parameter};

    </select>

 

2、引數個數為多個。

dao層方法：

    /*****1.註解傳參*****/

    public List<UserTab> selectUserListExceptUserId

    (@Param("USER_ID")String USER_ID,

     @Param("LIMIT_POS")int LIMIT_POS,

     @Param("LIMIT_SIZE")int LIMIT_SIZE);

對應的Mapper取值：

取值時應當注意，引數名字應該與dao層傳入的引數名字(@param處宣告的引數名)相同。

    /****註解傳參方式引數獲取****/

    <select id="selectUserListExceptUserId"

                resultMap="userResMap">

     

     select * from MH_USER

            where USER_ID!=#{USER_ID}

            and USER_STATE>9

            order by NICK_NAME

            limit #{LIMIT_POS},#{LIMIT_SIZE}

    </select>

3、引數為map的形式(常用)

mapper中使用map的key取值

dao中的方法:

    /*****1.引數為map*****/

    public List<Source> search(Map<String,Object> param);

     

    /***2.map的內部封裝***/

         Map<String,Object> param=new HashMap<String,Object>();

        param.put("page", (page-1)*pageSize);

        param.put("pageSize",pageSize);

        param.put("keyword","%"+keyword+"%");

        param.put("type",type);

        List<Source> sources=sourceDao.search(param);

對應的Mapper取值：

 <select id="search"

                parameterType="java.util.Map"

                resultType="com.bonc.wechat.entity.publicserver.Source">

     select * from wx_source

            where

      <if test="keyword != null and keyword != ''">

            (title like #{keyword(按map鍵取值)} or content like #{keyword}) and

             </if>

              type=#{type}

       order by ordernum asc

              limit #{page},#{pageSize};

    </select>

4、引數為物件(常用)

  1.mapper中使用物件中的屬性直接取值，在對映介面中的方法不加@Param

  2.【物件.屬性】取值：物件的名稱一定要在對映介面中的方法中宣告@Param並一致

dao中的方法:

    /*****使用物件傳參*****/

     public int addUserComment(UserComment UC);

 

    /*****物件中的屬性*****/

    private int id;

     private int department_id;

     private String telphone;

     private String content;

     private String createtime; 

對應的Mapper取值：

    <insert id="addUserComment"

                parameterType="com.bonc.wechat.entity.publicserver.UserComment">

     insert into wx_user_comment

                       (department_id,

                        telphone,

                        content,

                        createtime)

     values(#{department_id},

                       #{telphone},

                       #{content},

                       #{createtime});

    </insert>

*使用【物件.屬性】取值。

dao層：

   /******此示例中直接省去dao層，service直接繫結mapper層******/

     

    public PageResult findPanoramaPage(Page page) throws Exception{

        List<PageData> panoramaList = new ArrayList<PageData>();

        try {

     panoramaList = (List<PageData>)dao.findForList("PanoramaMapper.findPagePanorama", page);

     } catch (Exception e) {

     e.printStackTrace();

         }

     PageResult pageResult = new PageResult(page.getTotalResult(),panoramaList);

     return pageResult;

    }

對應的Mapper取值：

 <select id="findPagePanorama"

                parameterType="page"

                resultType="pd">

     

     SELECT

     a.id as id,

     a.project_code as projectCode,

     a.project_name as projectName,

     a.project_addr as projectAddr,

     a.project_type as projectType

     FROM

     calm_project a

     WHERE

     a.is_valid=1

     <if test="page.projectType != null and page.projectType != ''">

            AND a.project_type = #{page.projectType}

            </if>

     <if test="page.keyword != null and page.keyword != ''">

           AND (a.project_name LIKE '%${page.keyword}%' OR a.project_code LIKE '%${page.keyword}%')

            </if>

            ORDER BY

                 a.sort

               

    </select>

推薦使用第三和第四種，將所傳的資料在controller層或者service層封裝起來，傳入mapper檔案中取值。