Excel导出采用mvc的ExcelResult继承遇到的问题Npoi导出

 #region 构建Excel文档
            //创建Excel文件的对象
            NPOI.HSSF.UserModel.HSSFWorkbook book = new NPOI.HSSF.UserModel.HSSFWorkbook();
            NPOI.SS.UserModel.CellStyle style = book.CreateCellStyle();
            style.Alignment = NPOI.SS.UserModel.HorizontalAlignment.CENTER;
            style.VerticalAlignment = NPOI.SS.UserModel.VerticalAlignment.CENTER;
            ////设置边框格式
            style.BorderTop = NPOI.SS.UserModel.CellBorderType.THIN;
            style.BorderLeft = NPOI.SS.UserModel.CellBorderType.THIN;
            style.BorderRight = NPOI.SS.UserModel.CellBorderType.THIN;
            style.BorderBottom = NPOI.SS.UserModel.CellBorderType.THIN;

            //添加一个sheet
            NPOI.SS.UserModel.Sheet sheet1 = book.CreateSheet("Sheet1");
            //获取list数据
            NPOI.SS.UserModel.Row row1 = sheet1.CreateRow(0);
            SetColcumns(book, sheet1, style, 0, row1, "编号");
            SetColcumns(book, sheet1, style, 1, row1, "");
            SetColcumns(book, sheet1, style, 2, row1, "是否本人");
            for (int i = 0; i < 34; i++)
            {
                sheet1.SetColumnWidth(i, 20 * 256);
            }
            //将数据逐步写入sheet1各个行
            int num = 0;
            foreach (var item in cooperates)
            {
                NPOI.SS.UserModel.Row rowtemp = sheet1.CreateRow(num + 1);

                SetColcumns(book, sheet1, style, 0, rowtemp, item.ID.ToString());
                SetColcumns(book, sheet1, style, 1, rowtemp, item.UserName);
                SetColcumns(book, sheet1, style, 2, rowtemp, item.IsSelfStrc);
                num++;
            }
            byte[] data = null;
            using (MemoryStream ms = new MemoryStream())
            {
                book.Write(ms);
                ms.Flush();
                ms.Position = 0;
                data = ms.GetBuffer();
            }
            return File(data, "application/vnd.ms-excel", "信息" + DateTime.Now.ToString("yyyyMMddHHmmss") + ".xls");
            #endregion