springboot整合分页插件PageHelper

- 日理万妓 2022-10-14 00:55 75阅读 0赞

## 一. 概述 ##

> 后端开发80%都是查询操作, 而查询经常涉及到数据分页, 分页工具有很多, 本文介绍的是分页插件PageHelper, 工程基于springboot  
> 参考文章: [springBoot mybatis整合pageHelper][springBoot mybatis_pageHelper]

## 二.使用说明 ##

**1.导包**

<dependency>
        <groupId>com.github.pagehelper</groupId>
        <artifactId>pagehelper-spring-boot-starter</artifactId>
        <version>1.2.3</version>
    </dependency>

**2.YML配置**

pagehelper:
      autoRuntimeDialect: true
      reasonable: true
      supportMethodsArguments: true
      params: count=countSql

**3.分页使用示例**  
controller层

@RestController
    @RequestMapping("/pageHelperTest/")
    public class PageHelperTest{ 
        @Autowired
        private UserService userService;
        
       @RequestMapping("/pageHelperTest/{pageNum}/{pageSize}")
        public PageInfo<User> pageHelperTest(@PathVariable Integer pageNum, @PathVariable Integer pageSize){ 
            //调用方法进行分页查询
            return userService.findAll(pageNum, pageSize);
        }
    }

service层

@Service
    public class UserService{ 
        @Autowired
        private UserMapper userMapper;
        public PageInfo<User> findAll(int pageNum, int pageSize) { 
            // 设置分页参数; pageNum:页码, pageSize:每页大小
            PageHelper.startPage(pageNum,pageSize);
            // 执行sql查询方法查询所有数据, 会自动分页
            List<User> list = userMapper.findAll();
            return new PageInfo<User>(list);
        }
    }

**返回json结果示例**

{ 
      "pageNum": 3,
      "pageSize": 3,
      "size": 3,
      "startRow": 7,
      "endRow": 9,
      "total": 10,
      "pages": 4,
      "list": [
        { 
          "id": 9,
          "username": "bajie",
          "password": "123456",
          "createTime": "2019-06-21T16:00:00.000+0000",
          "trueName": "猪八戒",
          "remarks": null,
          "bz": null
        },
        { 
          "id": 10,
          "username": "wukong",
          "password": "123456",
          "createTime": "2019-06-21T16:00:00.000+0000",
          "trueName": "孙悟空",
          "remarks": null,
          "bz": null
        },
        { 
          "id": 11,
          "username": "shasheng",
          "password": "123456",
          "createTime": "2019-06-21T16:00:00.000+0000",
          "trueName": "沙悟净",
          "remarks": null,
          "bz": null
        }
      ],
      "prePage": 2,
      "nextPage": 4,
      "isFirstPage": false,
      "isLastPage": false,
      "hasPreviousPage": true,
      "hasNextPage": true,
      "navigatePages": 8,
      "navigatepageNums": [
        1,
        2,
        3,
        4
      ],
      "navigateFirstPage": 1,
      "navigateLastPage": 4,
      "firstPage": 1,
      "lastPage": 4
    }

**4.解释**  
其中：PageHelper.startPage(int PageNum,int PageSize):用来设置页面的位置和展示的数据条目数，我们设置每页展示5条数据。PageInfo用来封装页面信息，返回给前台界面。PageInfo中的一些我们需要用到的参数如下表：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjQwODQ0Nw_size_16_color_FFFFFF_t_70]  
**三.参考**  
[Springboot Mybatis使用pageHelper实现分页查询][Springboot Mybatis_pageHelper]  
[Spring Boot入门，整合Pagehelper分页插件  
][Spring Boot_Pagehelper_]

[springBoot mybatis_pageHelper]: https://www.jianshu.com/p/bb175218617a
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjQwODQ0Nw_size_16_color_FFFFFF_t_70]: /images/20221014/8c7158f637714c0b87cb81ce12001e69.png
[Springboot Mybatis_pageHelper]: https://blog.csdn.net/qq_35387940/article/details/91530234
[Spring Boot_Pagehelper_]: https://blog.csdn.net/qq_27317475/article/details/81168241