Npoi List DataTable导出一个Excel多个sheet 下载

1、nuget搜索安装Npoi

2、代码

public class UserInfo
  {
      public string Name { get; set; }
      public string Id { get; set; }
      public string Phone { get; set; }
  }
 
/// <summary>
      /// 生成excel文件到内存中
      /// </summary>
      /// <returns></returns>
      public void CreateExcel()
      {
          MemoryStream ms = new MemoryStream();
 
          List<UserInfo> listUser = new List<UserInfo>()
         {
             new UserInfo { Name="1", Id="1", Phone="1r" },
             new UserInfo { Name="2", Id="2", Phone="2r" },
             new UserInfo { Name="3", Id="3", Phone="3r" },
             new UserInfo { Name="4", Id="4", Phone="4r" },
             new UserInfo { Name="5", Id="5", Phone="5r" },
         };
 
          //创建工作簿对象
          var workbook = new HSSFWorkbook();
 
          #region DataTable数据
          //创建工作表
          ISheet sheet = workbook.CreateSheet("一个sheet");
          IRow row0 = sheet.CreateRow(0);
          row0.CreateCell(0).SetCellValue("用户Id");
          row0.CreateCell(1).SetCellValue("用户名称");
          row0.CreateCell(2).SetCellValue("用户备注信息");
 
           
          var dtSource = GetDataTable();
          for (int i = 0; i < dtSource.Rows.Count; i++)
          {
              row0 = sheet.CreateRow(i + 1);
              for (int j = 0; j < dtSource.Columns.Count; j++)
              {
                  row0.CreateCell(j).SetCellValue(dtSource.Rows[i][j].ToString());
              }
          }
 
          #endregion
 
          #region list数据
          ISheet sheet2 = workbook.CreateSheet("另一个sheet");
          IRow row2 = sheet2.CreateRow(0);
          row2.CreateCell(0).SetCellValue("用户Id2");
          row2.CreateCell(1).SetCellValue("用户名称2");
          row2.CreateCell(2).SetCellValue("用户备注信息2");
           
          for (int r = 1; r < listUser.Count; r++)
          {
              //创建行row
              IRow row = sheet2.CreateRow(r);
              row.CreateCell(0).SetCellValue(listUser[r].Id);
              row.CreateCell(1).SetCellValue(listUser[r].Name);
              row.CreateCell(2).SetCellValue(listUser[r].Phone);
          }
 
          #endregion
 
          workbook.Write(ms);
 
          ms.Flush();
          ms.Position = 0;
 
          var fileName = "测试Excel" + DateTime.Now.ToString("yyyyMMddHHmmss") + ".xlsx";//xls
          DownloadExcel(ms, fileName);
           
      }
 
      /// <summary>
      /// 生成http流下载文件
      /// </summary>
      /// <param name="ms"></param>
      /// <param name="fileName"></param>
      private static void DownloadExcel(MemoryStream ms, string fileName)
      {
          #region 处理IE、火狐等浏览器文件名乱码
          if (System.Web.HttpContext.Current.Request.ServerVariables["http_user_agent"].IndexOf("Firefox", StringComparison.Ordinal) != -1)
          {
              fileName = "=?UTF-8?B?" + Convert.ToBase64String(System.Text.Encoding.UTF8.GetBytes(fileName)) + "?=";
          }
          else
          {
              fileName = System.Web.HttpUtility.UrlEncode(fileName, System.Text.Encoding.UTF8);
              fileName = fileName.Replace("+", "%20");
          }
          #endregion
          System.Web.HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment;fileName=" + fileName);
          System.Web.HttpContext.Current.Response.AddHeader("Content-Length", ms.Length.ToString());
          System.Web.HttpContext.Current.Response.AddHeader("Content-Transfer-Encoding", "binary");
          System.Web.HttpContext.Current.Response.ContentType = "application/octet-stream;charset=utf-8";
          System.Web.HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.UTF8;
          System.Web.HttpContext.Current.Response.BinaryWrite(ms.ToArray());
      }
 
      /// <summary>
      /// 模拟DataTable
      /// </summary>
      /// <returns></returns>
      public DataTable GetDataTable()
      {
          DataTable tblDatas = new DataTable("Datas");
          DataColumn dc = null;
 
          dc = tblDatas.Columns.Add("Name", Type.GetType("System.String"));
          dc = tblDatas.Columns.Add("Id", Type.GetType("System.String"));
          dc = tblDatas.Columns.Add("Phone", Type.GetType("System.String"));
 
          DataRow newRow;
          newRow = tblDatas.NewRow();
          newRow["Name"] = "大话西游";
          newRow["Id"] = "2.0";
          newRow["Phone"] = "我很喜欢";
          tblDatas.Rows.Add(newRow);
 
          newRow = tblDatas.NewRow();
          newRow["Name"] = "梦幻西游";
          newRow["Id"] = "3.0";
          newRow["Phone"] = "比大话更幼稚";
          tblDatas.Rows.Add(newRow);
 
          return tblDatas;
      }

 引用：https://www.cnblogs.com/heifengwll/p/7016032.html