void DownloadForAccountIndex(IReadOnlyList<AccountInfoView> list)

        {

            NPOI.HSSF.UserModel.HSSFWorkbook book = new NPOI.HSSF.UserModel.HSSFWorkbook();

            NPOI.SS.UserModel.ISheet sheet = book.CreateSheet("账号数");

            int i = ;

            // 第一行：

            NPOI.SS.UserModel.IRow rowTitle = sheet.CreateRow();

            rowTitle.CreateCell(i++).SetCellValue("时间");

            rowTitle.CreateCell(i++).SetCellValue("累计账号数");

            rowTitle.CreateCell(i++).SetCellValue("新增账号数");

            int rowIndex = ;

            foreach (var item in list)

            {

                i = ;

                NPOI.SS.UserModel.IRow row = sheet.CreateRow(rowIndex);

                row.CreateCell(i++).SetCellValue(item.CreateMonth);

                row.CreateCell(i++).SetCellValue(item.AllCount);

                row.CreateCell(i++).SetCellValue(item.NewCount);

                rowIndex++;

            }

            // 写入到客户端

            System.IO.MemoryStream ms = new System.IO.MemoryStream();

            book.Write(ms);

            Response.AddHeader("Content-Disposition", string.Format("attachment; filename=账号数（{0}）.xls", DateTime.Now.ToString("yyyyMMdd")));

            Response.BinaryWrite(ms.ToArray());

            book = null;

            ms.Close();

            ms.Dispose();

            Response.Flush();

        }