1、分页查询的执行过程
在实际的项目开发过程中,分页显示是很常见的页面布局；下面我们来梳理一下常规操作中分页查询的执行过程：
- 页面发送ajax请求，将分页查询参数（page、pagesize、name等额外信息）提交到服务端
- 服务端（controller）接收页面提交的数据并调用Service查询数据
- Service调用Mapper操作数据库，查询分页数据
- Controller将查询到的分页数据响应给页面
- 页面接收到分页数据并通过前端组件（例如：ElementUI的Table组件）展示到页面上
2、页面发送ajax请求：
async init () { const params = { page: this.page, pageSize: this.pageSize, name: this.input ? this.input : undefined } await getMemberList(params).then(res => { if (String(res.code) === '1') { this.tableData = res.data.records || [] this.counts = res.data.total } }).catch(err => { this.$message.error('请求出错了：' + err) }) },
3、创建mybaitisPlus的配置类
首先创建一个mybaitisPlus的配置类，使用mplus提供的分页插件进行过滤查询
package com.tigerhhzz.wuaimai.config; import com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor; import com.baomidou.mybatisplus.extension.plugins.inner.PaginationInnerInterceptor; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; /** * 配置MP的分页插件 */ @Configuration public class MybatisPlusConfig { @Bean public MybatisPlusInterceptor mybatisPlusInterceptor(){ MybatisPlusInterceptor mybatisPlusInterceptor = new MybatisPlusInterceptor(); mybatisPlusInterceptor.addInnerInterceptor(new PaginationInnerInterceptor()); return mybatisPlusInterceptor; } }
3、写controller接口
然后在controller中写一个接口
/** * 员工信息分页查询 * @param page * @param pageSize * @param name * @return */ @GetMapping("/page") public R<Page> page(int page, int pageSize, String name){ log.info("page = {},pageSize = {},name = {}" ,page,pageSize,name); //构造分页构造器 Page pageInfo = new Page(page,pageSize); //构造条件构造器 LambdaQueryWrapper<Employee> queryWrapper = new LambdaQueryWrapper(); //添加过滤条件 queryWrapper.like(StringUtils.isNotEmpty(name),Employee::getName,name); //添加排序条件 queryWrapper.orderByDesc(Employee::getUpdateTime); //执行查询 employeeService.page(pageInfo,queryWrapper); return R.success(pageInfo); }
4、测试
响应给页面数据：
{ "code":1, "msg":null, "data":{ "records":[ { "id":1634812678390161409, "username":"123456", "name":"zhangsan", "password":"xxxxxxx", "phone":"13133333333", "sex":"1", "idNumber":"130111119801018111", "status":1, "createTime":[ 2023, 3, 12, 15, 4, 51 ], "updateTime":[ 2023, 3, 12, 15, 4, 51 ], "createUser":1, "updateUser":1 }, { "id":1, "username":"admin", "name":"管理员", "password":"xxxxxx", "phone":"13812312312", "sex":"1", "idNumber":"110101199001010047", "status":1, "createTime":[ 2021, 5, 6, 17, 20, 7 ], "updateTime":[ 2021, 5, 10, 2, 24, 9 ], "createUser":1, "updateUser":1 } ], "total":2, "size":10, "current":1, "orders":[ ], "optimizeCountSql":true, "hitCount":false, "countId":null, "maxLimit":null, "searchCount":true, "pages":1 }, "map":{ } }
