EasyExcel 复杂表头的导出（动态表头和静态表头）

问题：如图，1部分的表头是动态的根据日期变化，2部分是数据库对应的字段，静态不变的；

解决方案：如果不看1的部分，2部分+内容可以根据实体类+注解的方式导出，那么我们是不是可以先将动态表头1 写入到Excel中，然后再用注解+实体类的方式将2部分和内容写入到Excel中。

// 以下是伪代码参考，无法直接运行// 设置动态表头
List<String> head = new ArrayList<>();String name = String.format(sheetName, LocalDate.now().getYear(), LocalDate.now().getMonth().getValue());if (StringUtils.isNotBlank(publicityReq.getCountyId())) {name = name + "\n" + depart + departName;
}head.add(name);
headList.add(head);ExcelWriter excelWriter = EasyExcel.write(response.getOutputStream(), TPublicityInfo.class).build();
// 创建sheet
WriteSheet writeSheet = EasyExcel.writerSheet(String.format(sheetName, LocalDate.now().getYear(), LocalDate.now().getMonth().getValue())).needHead(Boolean.FALSE).build();
// 将动态表头写入sheet，new ArrayList<>()代表写入空数据
WriteTable writeTable0 = EasyExcel.writerTable(0).head(headList).registerWriteHandler(new OnceAbsoluteMergeStrategy(0, 2, 0, 7)).needHead(Boolean.TRUE).build();excelWriter.write(new ArrayList<>(), writeSheet, writeTable0);
// 将静态表头+内容写入sheet，tPublicityInfos代表内容数据
WriteTable writeTable2 = EasyExcel.writerTable(3).head(TPublicityInfo.class).relativeHeadRowIndex(2).needHead(Boolean.TRUE).build();excelWriter.write(tPublicityInfos, writeSheet, writeTable2);
excelWriter.finish();

下边是项目中的完整代码，可以做简单参考

public void exportExcel(Principal principal, HttpServletResponse response, PublicityInfoReq publicityReq) throws IOException {String sheetName = "%s年%s月xxxx";String depart = "单位：";String personId = AuthenticationInfo.getUserId(principal);String departsCode = "";if (StringUtils.isNotEmpty(publicityReq.getCorpId())) {DepartInfo departInfo = iDepartSCodeService.getVDeptById(publicityReq.getCorpId());departsCode = departInfo.getDepartScode();} else {departsCode = iDepartSCodeService.getDeptScode(personId);}publicityReq.setDepartsCode(departsCode);List<TPublicityInfo> tPublicityInfos = publicityMapper.listByPublicity(publicityReq);if (CollectionUtils.isNotEmpty(tPublicityInfos)) {for (int i = 0; i < tPublicityInfos.size(); i++) {TPublicityInfo tPublicityInfo = tPublicityInfos.get(i);tPublicityInfo.setNum(i+1);}}List<String> departNames = this.baseMapper.selectDepartNameByDepartId(publicityReq.getCountyId());String departName = "";if (CollectionUtils.isNotEmpty(departNames) && departNames.size() == 1) {departName = departNames.get(0);}List<List<String>> headList = new ArrayList<>();List<String> head = new ArrayList<>();String name = String.format(sheetName, LocalDate.now().getYear(), LocalDate.now().getMonth().getValue());if (StringUtils.isNotBlank(publicityReq.getCountyId())) {name = name + "\n" + depart + departName;}head.add(name);headList.add(head);ExcelWriter excelWriter = EasyExcel.write(response.getOutputStream(), TPublicityInfo.class).build();WriteSheet writeSheet = EasyExcel.writerSheet(String.format(sheetName, LocalDate.now().getYear(), LocalDate.now().getMonth().getValue())).needHead(Boolean.FALSE).build();WriteTable writeTable0 = EasyExcel.writerTable(0).head(headList).registerWriteHandler(new OnceAbsoluteMergeStrategy(0, 2, 0, 7)).needHead(Boolean.TRUE).build();excelWriter.write(new ArrayList<>(), writeSheet, writeTable0);WriteTable writeTable2 = EasyExcel.writerTable(3).head(TPublicityInfo.class).relativeHeadRowIndex(2).needHead(Boolean.TRUE).build();excelWriter.write(tPublicityInfos, writeSheet, writeTable2);excelWriter.finish();
}