excel导出功能第二种方法

public static void Export(DataTable Dt, string FileName, HttpResponse Response, bool AppendHeader)
      {
          StringBuilder sb = new StringBuilder();
          int countOfColumns = Dt.Columns.Count;
          int countOfRows = Dt.Rows.Count;
          if (AppendHeader)
          {
              for (int indexOfCl = 0; indexOfCl < countOfColumns - 1; indexOfCl++)
              {
                  sb.Append(Dt.Columns[indexOfCl] + "\t");
              }
              if (countOfColumns > 0)
              {
                  sb.Append(Dt.Columns[countOfColumns - 1] + "\n");
              }
          }
          for (int indexOfRow = 0; indexOfRow < countOfRows; indexOfRow++)
          {
              for (int indexOfCl = 0; indexOfCl < countOfColumns; indexOfCl++)
              {
                  sb.Append(Dt.Rows[indexOfRow][indexOfCl] + "\t");
              }
              sb.Append("\n");
          }
          Response.Clear();
          Response.ClearContent();
          Response.ClearHeaders();
          Response.ContentType = "application/octet-stream";
          Response.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");
          Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(Convert.ToString(FileName), System.Text.Encoding.UTF8));
          Response.Write(sb.ToString());
          Response.Flush();
          Response.End();
      }

var data1 = from f in siteData.已投稿列表
                               where (BeginTime.Value.Trim() != "" && EndTime.Value.Trim() != "") ?
                               (f.SubmittedDate >= Convert.ToDateTime(BeginTime.Value.Trim()))
                               && f.SubmittedDate <= Convert.ToDateTime(EndTime.Value.Trim()).AddDays(1) : 1 == 1
                               where f.Department == UserDept
                               group f by f.Department into g
                               where keyword != "" ? g.Key != null ? g.Key.Contains(keyword) : 3 == 3 : 2 == 2
                               orderby g.Count() descending
                               select new
                               {
                                   类别 = g.Key == null ? "无部门" : g.Key,
                                   文章次数 = g.Count(),
                                   已采纳数 = g.Count(o => o.HandleState == "实际采用")
                               };
                   if (data1 != null)
                   {
                       DataTable dt = new DataTable();
                       dt.Columns.Add("部门", typeof(string));
                       dt.Columns.Add("投稿数量", typeof(string));
                       dt.Columns.Add("已采纳数", typeof(string));
                       dt.Rows.Add(new object[] { "部门", "投稿数量", "已采纳数" });
                       for (int i = 0; i < data1.Count(); i++)
                       {
                           dt.Rows.Add(new object[] { data1.ElementAt(i).类别, data1.ElementAt(i).文章次数, data1.ElementAt(i).已采纳数 });
 
                       }
                       CoolFuncs.Export(dt, "部门投稿统计.xls", Response, false);
                   }