保姆级基础java用Easy Excel导出数据

前端我用的是vue写的代码  

导出只需要这一行代码

<el-button @click="exportExcel"> 导出</el-button>

这里面我导出是根据查询的条件导出查询的内容

exportExcel() {
这行代码是要获取城市的名称
  const city = this.formItem.busiRegCityCode || '';
这行是要获取取区县的名称
  const county = this.formItem.busiRegCountyCode || '';
这里是获取网格
  const grid = this.formItem.busiRegGridCode || '';
这里是获取日期的年月
  let date = new Date(this.formItem.createMonth);
  const year = date.getFullYear();
  let month = date.getMonth() + 1;
  month = month < 10 ? '0' + month : month.toString();
  const formatDate =`${year}-${month}`;
以上的是我自己的业务逻辑代码  仅供参考 具体需要自己的业务逻辑去改
获取到自己url路径   路径需要自己配  我的路径是放到路由里面了  所以这个根据自己的url来配
let url = this.$api.url.businessDetail.export;
// 创建一个 Map 对象来存储查询参数
      let params = new Map();
      params.set('city', city);
      params.set('county', county);
      params.set('grid', grid);
      params.set('createMonth', formatDate);

// 使用 URLSearchParams 对象来构建查询字符串
      let urlParams = new URLSearchParams(params);

// 将查询字符串附加到 URL
      url += '?' + urlParams.toString();

// 重定向到 URL
      window.location = url;
    },

以上是我写的业务前端代码

接下来是后端代码

Controller层 我是用的最笨的方法  把条件全都拿出来了 然后一个个去请求  练手的可以试试

@RequestMapping("/exportExcel")
public void exportExcel( @RequestParam("city") String city,
                         @RequestParam("county") String county,
                         @RequestParam("grid") String grid,
                         @RequestParam("createMonth") String createMonth,HttpServletResponse response ) throws IOException {

    iBusinessDetailService.generateExcel(city,county,grid,createMonth,response);

}

service层 

public interface IBusinessDetailService {
    void generateExcel(String city, String county, String grid,String createMonth ,HttpServletResponse response) throws IOException;
}

serviceImpl层 

@Override
    public void generateExcel(String city, String county, String grid, String createMonth, HttpServletResponse response) throws IOException {
//这下面都是我的业务需求 可以不必看 我只是把2024-12这种格式拆成2024和12放到年和月里面了        
String[] parts = createMonth.split("-");
        if (parts.length != 2) {
            throw new IllegalArgumentException("Invalid createMonth format: " + createMonth);
        }
        String year = parts[0];
        String month = parts[1];
//去数据库里查数据放到list里面
        List<BusinessDetailVO> dataList = businessDetailMapper.getExPost(city, county, grid, year, month, response);

        // 定义表头样式
        WriteCellStyle headWriteCellStyle = new WriteCellStyle();
        headWriteCellStyle.setHorizontalAlignment(HorizontalAlignment.CENTER); // 居中对齐
        headWriteCellStyle.setVerticalAlignment(VerticalAlignment.CENTER); // 垂直居中对齐
        headWriteCellStyle.setBorderBottom(BorderStyle.THIN); // 下边框
        headWriteCellStyle.setBorderTop(BorderStyle.THIN); // 上边框
        headWriteCellStyle.setBorderLeft(BorderStyle.THIN); // 左边框
        headWriteCellStyle.setBorderRight(BorderStyle.THIN); // 右边框
        headWriteCellStyle.setFillForegroundColor(IndexedColors.GREY_25_PERCENT.getIndex()); // 背景颜色

        // 定义内容样式
        WriteCellStyle contentWriteCellStyle = new WriteCellStyle();
        contentWriteCellStyle.setHorizontalAlignment(HorizontalAlignment.LEFT); // 水平左对齐
        contentWriteCellStyle.setVerticalAlignment(VerticalAlignment.CENTER); // 垂直居中对齐
        contentWriteCellStyle.setBorderBottom(BorderStyle.THIN); // 下边框
        contentWriteCellStyle.setBorderTop(BorderStyle.THIN); // 上边框
        contentWriteCellStyle.setBorderLeft(BorderStyle.THIN); // 左边框
        contentWriteCellStyle.setBorderRight(BorderStyle.THIN); // 右边框

        // 创建样式策略
        HorizontalCellStyleStrategy styleStrategy = new HorizontalCellStyleStrategy(headWriteCellStyle, contentWriteCellStyle);
以上从 // 定义表头样式到创建样式策略是可以不用要的 就是为了让表格变得更好看而已，如果看不明白 可以去EasyExcel官方文档去看看

        // 设置响应头
        response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
        response.setCharacterEncoding("utf-8");
        String fileName = URLEncoder.encode("网格通业务办理量明细", "UTF-8").replaceAll("\\+", "%20");
        response.setHeader("Content-disposition", "attachment;filename*=utf-8''" + fileName + ".xlsx");

        // 写入数据并应用样式策略  里面你需要定义一个实体类 BusinessDetailVO.class这种的 定义是为了把你需要的数据通过实体类导出去  
        EasyExcel.write(response.getOutputStream(), BusinessDetailVO.class)
                .registerWriteHandler(styleStrategy)
                .sheet("网格通业务办理量明细")
                .doWrite(dataList);
    }

BusinessDetailVO 实体类   @ExcelProperty(value = "地市")注解是用来定义表头的 

public class BusinessDetailVO implements Serializable {

    private static final long serialVersionUID = -2756710144226695139L;
    private String id;
    @ExcelProperty(value = "地市")
    private String eparchyName;

    @ExcelProperty(value = "区县")
    private String countryName;

    @ExcelProperty(value = "网格")
    private String  gridName;



    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getEparchyName() {
        return eparchyName;
    }

    public void setEparchyName(String eparchyName) {
        this.eparchyName = eparchyName;
    }

    public String getCountryName() {
        return countryName;
    }

    public void setCountryName(String countryName) {
        this.countryName = countryName;
    }

    public String getGridName() {
        return gridName;
    }

    public void setGridName(String gridName) {
        this.gridName = gridName;
    }

Mapper层 

    List<BusinessDetailVO> getExPost( @RequestParam("city") String city,
                                      @RequestParam("county") String county,
                                      @RequestParam("grid") String grid,
                                      @RequestParam("year") String year,
                                      @RequestParam("month") String month,
                                     HttpServletResponse response);

后面你就根据你的需求去mapper.xml里面去写sql就行了