NET Core导出Excel表格

1、首先用到Get包

NPOI

2、命名空间

using NPOI.HSSF.UserModel;
using NPOI.SS.UserModel;
using NPOI.XSSF.UserModel;

3、

[HttpGet]
 public IActionResult Excelexport(){
            var lifetimeScop = Container.BeginLifetimeScope();
            ICraftsmanService service = lifetimeScop.Resolve();
            var query = service.Postlist(o => true).ToList();
            //var currentUseId = User.FindFirst("sub").Value;
            var currentUseId = "craftsman";

            var rootPath = "/Upload/DownloadXls";
            if (System.IO.Directory.Exists(rootPath) == false)//判断指定的文件夹是否存在
                System.IO.Directory.CreateDirectory(rootPath);//创建指定路径的文件夹

            var newFile = rootPath + "/" + currentUseId + ".xls";
            if (System.IO.File.Exists(newFile))//判断文件是否存在
            {
                System.IO.File.Delete(newFile);//存在删除
            }

            using (var fs = new FileStream(newFile, FileMode.Create, FileAccess.Write))
            {
                //HSSFWorkbook workbook = new HSSFWorkbook();.xls（选用xls的话，最后返回下载的后缀名改为xls）
                XSSFWorkbook workbook = new XSSFWorkbook();//.xlsx，（推荐xlsx，2007版本以上都是xlsx的）
                var sheet = workbook.CreateSheet("orders");

                var header = sheet.CreateRow(0);
                header.CreateCell(0).SetCellValue("证书类型");
                header.CreateCell(1).SetCellValue("姓名");
                header.CreateCell(2).SetCellValue("性别");
                header.CreateCell(3).SetCellValue("学历");
                header.CreateCell(4).SetCellValue("手机号");
                header.CreateCell(5).SetCellValue("身份证号");
                header.CreateCell(6).SetCellValue("户籍地址");
                header.CreateCell(7).SetCellValue("常住地址");
                header.CreateCell(8).SetCellValue("头像");
                header.CreateCell(9).SetCellValue("身份证正面");
                header.CreateCell(10).SetCellValue("身份证反面");
                header.CreateCell(11).SetCellValue("所属乡镇");
                header.CreateCell(12).SetCellValue("证书链接");
                header.CreateCell(13).SetCellValue("证书编号");
                header.CreateCell(14).SetCellValue("证书有效期");

                var rowIndex = 1;
                for (int i = 0; i < query.Count; i++)
                {
                    var datarow = sheet.CreateRow(rowIndex);

                    datarow.CreateCell(0).SetCellValue(query[i].CertificateType);
                    datarow.CreateCell(1).SetCellValue(query[i].CraftsmanName);
                    datarow.CreateCell(2).SetCellValue(query[i].CraftsmanSex);
                    datarow.CreateCell(3).SetCellValue(query[i].CraftsmanEducation);
                    datarow.CreateCell(4).SetCellValue(query[i].CraftsmanPhone);
                    datarow.CreateCell(5).SetCellValue(query[i].IdCard);
                    datarow.CreateCell(6).SetCellValue(query[i].HjAddress);
                    datarow.CreateCell(7).SetCellValue(query[i].CzAddress);
                    datarow.CreateCell(8).SetCellValue(query[i].CraftsmanUrl);
                    datarow.CreateCell(9).SetCellValue(query[i].IcFrontUrl);
                    datarow.CreateCell(10).SetCellValue(query[i].IcBackUrl);
                    datarow.CreateCell(11).SetCellValue(query[i].Township);
                    datarow.CreateCell(12).SetCellValue(query[i].CertificateUrl);
                    datarow.CreateCell(13).SetCellValue(query[i].CertificateId);
                    datarow.CreateCell(14).SetCellValue(query[i].CertificateTimes);

                    rowIndex++;
                }
                workbook.Write(fs);
            }

            var memory = new MemoryStream();
            using (var stream = new FileStream(newFile, FileMode.Open))
            {
                stream.CopyTo(memory);//从一个流写入另一个流
            }
            memory.Position = 0;//设置流的当前位置
            return return File(memory, "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet", "工匠信息.xlsx");
}