导入Excel文件而不单击列并使用NPOI保存它

Question

如果我导出一个Excel并导入它（不打开它并单击并保存它），那么Excel中的第二个列在DataTable中是不可读的。

如果我在打开它并单击任何列并保存后导入同一个文件，那么导入Excel就成功了。

   int rowNumber = 0;
        int cellNo = 0;              
    //Create new Excel workbook             
        var workbook = new NPOI.HSSF.UserModel.HSSFWorkbook();

        NPOI.SS.UserModel.DataFormat accountingNewFormat = workbook.CreateDataFormat();

        CellStyle headerCellStyle = workbook.CreateCellStyle();
        headerCellStyle.DataFormat = accountingNewFormat.GetFormat("Text");

    //Create new Excel sheet             
        var sheet = workbook.CreateSheet("Equipment List");             
   // (Optional) set the width of the columns             
        sheet.SetColumnWidth(0, 30 * 256);
        sheet.SetColumnWidth(1, 20 * 256);

    //Create a header row             
        var headerRow = sheet.CreateRow(rowNumber++);
        headerRow.CreateCell(cellNo++).SetCellValue("ColumnName");
        headerRow.CreateCell(cellNo++).SetCellValue("ConstantValue");


       // cell.CellStyle.DataFormat = accountingNewFormat.GetFormat("General");

   // (Optional) freeze the header row so it is not scrolled             
        sheet.CreateFreezePane(0, 1, 0, 1); 

   // Populate the sheet with values from the grid data                         

        for (int x = 0; x < 2;x++ )
        {
            cellNo = 0;
            //   Create a new row                 
            var row = sheet.CreateRow(rowNumber++);
            row.CreateCell(cellNo++).SetCellValue("raj"+x);
            row.CreateCell(cellNo).SetCellValue("123");
        }

        //Write the workbook to a memory stream             
        System.IO.MemoryStream output = new System.IO.MemoryStream();
        workbook.Write(output);             //Return the result to the end user       

        //File(output.ToArray(),            //The binary data of the XLS file             
        //    "application/vnd.ms-excel",
        //    //MIME type of Excel files             
        //    "EquipmentList_" + DateTime.Now.ToString("dd/MM/yyyy hh:mm") + ".xls");
        ////Suggested file name in the "Save as" dialog which will be displayed to the end user  


        System.Web.HttpResponse Response = System.Web.HttpContext.Current.Response;
        Response.ContentType = "application/vnd.ms-excel";
        //Response.AddHeader("Content-Disposition", string.Format("attachment;filename={0}", HttpContext.Current.Server.MapPath("~/MasterPDF/" + filename)));
        Response.AppendHeader("Content-disposition", "attachment; filename=" + "rajdeep_TempFile.xls");
        Response.Clear();

        Response.BinaryWrite(WriteToStream_constant(workbook).GetBuffer());
        Response.End();