NPOI导出excel2007

#region NPOI导出Excel2007到xlsx
        /// <summary>
        /// 导出excel到xlsx
        /// </summary>
        /// <param name="dt">datatable数据源</param>
        /// <param name="strHeaderText">表头</param>
        /// <param name="columnNames">列头</param>
        /// <returns></returns>
        private static MemoryStream ExportXlsx(DataTable dt, string strHeaderText, string[] columnNames)
        {
            if (columnNames != null && columnNames.Length != dt.Columns.Count)
            {
                throw new ArgumentException("参数不正确:columnNames,数组元素的个数需要和数据源列的数量相同!");
            }

            XSSFWorkbook workbook = new XSSFWorkbook();
            ISheet sheet = null;

            string sheetName = "Sheet1";
            if (!string.IsNullOrEmpty(dt.TableName))
            {
                sheetName = dt.TableName;
            }
            sheet = workbook.CreateSheet(sheetName);
            int rowIndex = 0;

            #region 表头及样式
            {
                IRow headerRow = sheet.CreateRow(0);
                headerRow.HeightInPoints = 25;
                headerRow.CreateCell(0).SetCellValue(strHeaderText);

                ICellStyle headStyle = workbook.CreateCellStyle();
                headStyle.Alignment = HorizontalAlignment.Center;
                IFont font = workbook.CreateFont();
                font.FontHeightInPoints = 20;
                font.Boldweight = 700;
                headStyle.SetFont(font);
                headerRow.GetCell(0).CellStyle = headStyle;
                sheet.AddMergedRegion(new CellRangeAddress(0, 0, 0, dt.Columns.Count - 1));
            }
            #endregion

            #region 列头及样式
            {
                XSSFRow headerRow = (XSSFRow)sheet.CreateRow(1);

                ICellStyle headStyle = workbook.CreateCellStyle();
                headStyle.Alignment = HorizontalAlignment.Center;
                IFont font = workbook.CreateFont();
                font.FontHeightInPoints = 10;
                font.Boldweight = 700;
                headStyle.SetFont(font);

                foreach (DataColumn column in dt.Columns)
                {
                    headerRow.CreateCell(column.Ordinal).SetCellValue(columnNames[rowIndex]);
                    headerRow.GetCell(column.Ordinal).CellStyle = headStyle;
                    rowIndex++;
                }
            }
            #endregion

            #region 填充内容
            rowIndex = 1;
            foreach (DataRow row in dt.Rows)
            {
                rowIndex++;
                XSSFRow dataRow = (XSSFRow)sheet.CreateRow(rowIndex);
                foreach (DataColumn column in dt.Columns)
                {
                    string drValue = row[column].ToString();
                    dataRow.CreateCell(column.Ordinal).SetCellValue(drValue);
                }
            }
            #endregion


            MemoryStream ms = new MemoryStream();

            workbook.Write(ms);
            ms.Flush();

            return ms;
        }
        /// <summary>
        /// web导出
        /// </summary>
        /// <param name="dt">数据源</param>
        /// <param name="strFileName">表头</param>
        /// <param name="columnNames">列头</param>
        public static void ExportXlsxByWeb(DataTable dt, string strFileName, string[] columnNames)
        {
            HttpContext curContext = HttpContext.Current;
            MemoryStream ms = ExportXlsx(dt, strFileName, columnNames);
            curContext.Response.AppendHeader("Content-Disposition",
                "attachment;filename=" + HttpUtility.UrlEncode(strFileName + DateTime.Now.ToString("yyyyMMddhhmmssfff"), Encoding.UTF8) + ".xlsx");
            curContext.Response.AddHeader("Content-Length", ms.ToArray().Length.ToString());
            curContext.Response.ContentEncoding = Encoding.UTF8;
            curContext.Response.BinaryWrite(ms.ToArray());
            ms.Close();
            ms.Dispose();
            curContext.Response.End();
        }
        
        #endregion