MybatisPlus - [04] 分页

limit m,n、PageHelper、MyBatisPlus分页插件

001 || MybatisPlus分页插件

（1）引入maven依赖

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-boot-starter</artifactId>
    <version>3.5.4</version>
</dependency>

（2）在MybatisPlusConfig中进行配置

package com.harley.config;

import com.baomidou.mybatisplus.annotation.DbType;
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;

@Configuration
public class MybatisPlusConfig {

    @Bean
    public MybatisPlusInterceptor paginationInterceptor() {
        MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();
        // 指定数据库类型
        interceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.MYSQL)); // 如果配置多个插件, 切记分页最后添加
        // 如果有多数据源可以不配具体类型, 否则都建议配上具体的 DbType
        return interceptor;
    }
}

（3）测试

@Test
void testPage(){
    Page<User> page = new Page<>(1, 5);
    userMapper.selectPage(page, null);
    page.getRecords().forEach(System.out::println);

}

（4）Service层

package com.harley.service;

import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.IService;
import com.harley.entity.Account;
import java.util.List;

/**
 * <p>
 * 需要同步元数据的表配置 服务类
 * </p>
 *
 * @author harley
 * @since 2024-12-17
 */
public interface AccountService extends IService<Account> {

    IPage<Account> getRecordPage(int currentPage, int pageSize, String keyword);

}

（5）实现类

package com.harley.service.impl;

import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.harley.entity.Account;
import com.harley.mapper.AccountMapper;
import com.harley.service.AccountService;

/**
 * <p>
 * 需要同步元数据的表配置 服务实现类
 * </p>
 *
 * @author harley
 * @since 2024-12-17
 */
@Service
public class AccountServiceImpl extends ServiceImpl<AccountMapper, Account> implements AccountService {

    @Autowired
    private AccountMapper accountMapper;

    @Override
    public IPage<Account> getRecordPage(int currentPage,int pageSize,String keyword){
        // 创建Page对象, 传入当前页和每页记录数
        Page<Account> page = new Page<>(currentPage, pageSize);
        LambdaQueryWrapper<Account> lambdaQueryWrapper = new LambdaQueryWrapper<>();
        // 根据更新时间降序排列
        lambdaQueryWrapper.orderByDesc(Account::getUpdateTime);
        // 如果关键字非空,则进行模糊查询
        if( keyword != null && !keyword.isEmpty()){
            lambdaQueryWrapper.like(Account::getName,keyword)
                    .or()
                    .like(Account::getUsername,keyword);
        }

        // 进行分页查询
        return accountMapper.selectPage(page, lambdaQueryWrapper);
    }

}

（6）Controller层

package com.harley.controller;

import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.harley.entity.Account;
import com.harley.mapper.AccountMapper;
import com.harley.service.AccountService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

/**
 *
 * @author harley
 * @since 2024-12-17
 */
@RestController
@RequestMapping("/account")
public class SyncTblConfigController {

    @Autowired
    private AccountService accountService;

    @GetMapping("/getRecordPage")
    public IPage<Account> getRecordPage(@RequestParam Integer currentPage,
                                        @RequestParam Integer pageSize,
                                        @RequestParam(value = "keyword", defaultValue = "", required = false) String keyword){

        return accountService.getRecordPage(currentPage, pageSize, keyword);
    }

}

（7）vue页面

<template>
    <div>
        <div class="page-main">
        <!-- 搜索框和按钮 -->
        <div class="search-bar">
            <el-input placeholder="请输入数据库名或表名关键字" v-model="query.keyword" style="width:500px;" clearable @input="debouncedFetchRecords">
              <!-- <template #append>
                  <el-button type="primary" icon="el-icon-search" @click="fetchrecords">搜索</el-button>
              </template> -->
            </el-input>
            <el-button type="success" style="margin-left:30px;" @click="showDialog('add',row=null)">新增</el-button>
        </div>
        </div>
        <el-table :data="records" style="width: 100%">
          <el-table-column prop="id" label="序号" width="auto"></el-table-column>
          <el-table-column prop="databaseName" label="数据库" width="auto"></el-table-column>
          <el-table-column prop="tableName" label="表名" width="400"></el-table-column>
          <el-table-column prop="operator" label="操作人员">
              <template slot-scope="scope">{{ scope.row.operator || 'N/A'}}</template>
          </el-table-column>
          <el-table-column prop="createTime" label="创建时间"></el-table-column>
          <el-table-column prop="updateTime" label="更新时间"></el-table-column>
          <el-table-column prop="owner" label="owner"></el-table-column>
          <el-table-column label="操作" width="200">
              <template slot-scope="scope">
              <el-button size="mini" type="primary" @click="showDialog('edit',scope.row)"><i class="el-icon-edit" style="font-size: 15px;"></i> 编辑</el-button>
              <!-- <el-button size="mini" type="danger" @click="deleteRecord(scope.row.id)"><i class="el-icon-delete" style="font-size: 15px;"></i> 删除</el-button> -->
              </template>
          </el-table-column>
        </el-table>
        <!-- 分页控件 -->
        <el-pagination
          @size-change="handleSizeChange"
          @current-change="handleCurrentChange"
          :current-page="query.pageNum"
          :page-size="query.pageSize"
          :total="query.total"
          layout="total, sizes, prev, pager, next, jumper"
          :page-sizes="[5, 10]"
          style="text-align: center;"
        ></el-pagination>
        <!-- 新增/编辑对话框 -->
        <el-dialog :title="dialogTitle" :visible.sync="dialogVisible" width="30%">
        <el-form :model="form" :rules="rules" ref="form" label-width="100px">
          <el-form-item label="编号" prop="id">
            <el-input v-model="form.id" disabled></el-input>
          </el-form-item>
          <el-form-item label="数据库" prop="databaseName">
            <el-input v-model="form.databaseName"></el-input>
          </el-form-item>
          <el-form-item label="表名" prop="tableName">
            <el-input v-model.number="form.tableName"></el-input>
          </el-form-item>
          <el-form-item label="操作人员" prop="operator">
            <el-input v-model.number="form.operator"></el-input>
          </el-form-item>
          <el-form-item label="owner" prop="owner">
            <el-input v-model.number="form.owner"></el-input>
          </el-form-item>
        </el-form>
        <span slot="footer" class="dialog-footer">
            <el-button @click="dialogVisible = false">取 消</el-button> <!-- 点击取消按钮,遮罩层隐藏 -->
            <el-button type="primary" @click="handleSubmit">确 定</el-button>
        </span>
        </el-dialog>

    </div>

</template>

<script>
import axios from 'axios';
import { debounce } from 'lodash';

export default {
  name: 'SyncTblConfigPage',
  data() {
      return {
        query: {
          keyword: '',
          pageNum: 0,
          pageSize: 5,
          total: 10,
        },
        tableData: [],
        loading: false,
        records: [],
        editVDialogVisible: false,
        selectedRecord: null,
        dialogVisible: false, // 控制对话框的显示与隐藏,默认为隐藏
        dialogTitle: '', // 对话框标题
        form: {
            id: null,
            name: '',
            username: '',
            password: '',
            comment: '',
        },// 表单数据
        rules: {
            databaseName: [{ required: true, message: '数据库名不能为空', trigger: 'blur' }],
            tableName: [{ required: true, message: '表名不能为空', trigger: 'blur' }],
            operator: [{ required: false, message: '请输入操作人员', trigger: 'blur' }],
            owner: [{ required: true, message: 'owner不能为空', trigger: 'blur' }],
        }, // 表单验证规则
        currentRow: null, // 当前编辑的行数据
      };
  },
  created() {
    this.fetchrecords();
    this.debouncedFetchRecords = debounce(this.fetchrecords, 500);
    this.$watch('query.keyword', (newVal) => {
      if (!newVal) {
        this.fetchrecords();
      }else {
        this.debouncedFetchRecords = debounce(this.fetchrecords, 500);
      }
    });
  },
  methods: {
    async fetchrecords() {
      await axios.get('/api/syncTblConfig/getRecordPage',{
        params: {
          currentPage: this.query.pageNum,
          pageSize: this.query.pageSize,
          keyword: this.query.keyword,
        }
      }).then(response => {
        this.records = response.data.records.map(Record => ({
          id: Record.id,
          databaseName: Record.databaseName,
          tableName: Record.tableName,
          operator: Record.operator,
          createTime: new Date(Record.createTime).toLocaleString(),
          updateTime: new Date(Record.updateTime).toLocaleString(),
          owner: Record.owner,
        }));
        this.query.total = response.data.total;
        this.query.pageNum = response.data.current;
        this.query.pageSize = response.data.size;
      }).catch(error => {
        console.error('There was an error fetching the records!', error);
      });

    },
    showDialog(type, row = null) {
      this.dialogVisible = true;
      this.dialogTitle = type === 'add' ? '新增记录' : '编辑记录';
      this.currentRow = row;

      if (type === 'add') {
        this.$refs.form && this.$refs.form.resetFields();
      } else if (row) {
        this.form = { ...row }; // 使用展开运算符复制对象以避免引用问题
      }
    },
    async deleteRecord(id){
      try{
        const response = await axios.get(`/api/Record/del?id=${id}`);
        console.log('已删除: ' + response.data)
        await this.fetchrecords();
      }catch(error){
        console.error('删除失败', error);
      }
    },
    handleSubmit() {
      if (this.dialogTitle === '新增记录') {
        this.$refs.form.validate((valid) => {
          if (valid) {
            axios.post('/api/Record/addRecord', this.form)
              .then(response => {
                console.log('新增成功: ' + response.data);
                this.$message({
                  message: '新增账号',
                  type: 'success'
                });
                this.dialogVisible = false;
                this.records.push({ ...this.form });
                this.fetchrecords();
              })
              .catch(error => {
                console.error('新增账号失败', error);
                this.$message({
                  message: '新增账号失败',
                  type: 'error'
                });
            });
          } else {
            console.log('表单验证失败!!');
            return false;
          }
        });

      } else if(this.dialogTitle === '编辑记录'){
        this.$refs.form.validate((valid) => {
          if (valid) {
            axios.put(`/api/Record/updateRecord/${this.form.id}`, this.form)
              .then(response => {
                console.log('更新成功: ' + response.data);
                this.$message({
                  message: response.data,
                  type: 'success'
                });
                this.dialogVisible = false;
                const index = this.records.findIndex(Record => Record.id === this.form.id);
                if (index !== -1) {
                  this.$set(this.records,index, { ...this.form });
                }
                this.fetchrecords();
              })
              .catch(error => {
                console.error('更新失败', error);
                this.$message({
                  message: '更新失败',
                  type: 'error'
                });
            });
          } else {
            console.log('表单验证失败!!');
            return false;
          }
        });
      }
    },
    handleSizeChange(newSize) {
      console.log(`每页 ${newSize} 条`);
      this.query.pageSize = newSize;
      this.fetchrecords();
    },
    handleCurrentChange(newPage) {
      console.log(`当前页: ${newPage}`);
      this.query.pageNum = newPage;
      this.fetchrecords();
    },
    debouncedFetchRecords: debounce(function(){this.fetchRecords()}, 500).bind(this),
  }
}
</script>
<style scoped>

</style>

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