用NOPI将图片二进制流导出到Excel

这儿采取的是将图片的二进制流导出到Excel，直接上代码：

        /// <summary>
        /// DataTable导出到Excel的MemoryStream
        /// </summary>
        /// <param name="dtSource">源DataTable</param>
        /// <param name="strHeaderText">表头文本</param>
        /// <param name="strSheetName">工作表名称</param>
        public static MemoryStream Export(DataTable dtSource, string strHeaderText, string strSheetName, string[] oldColumnNames, string[] newColumnNames)
        {
            if (oldColumnNames.Length != newColumnNames.Length)
            {
                return new MemoryStream();
            }
            HSSFWorkbook workbook = new HSSFWorkbook();
            ISheet sheet = workbook.CreateSheet(strSheetName);

            #region 右击文件 属性信息
            {
                DocumentSummaryInformation dsi = PropertySetFactory.CreateDocumentSummaryInformation();
                dsi.Company = "http://....../";
                workbook.DocumentSummaryInformation = dsi;

                SummaryInformation si = PropertySetFactory.CreateSummaryInformation();
                if (HttpContext.Current.Session["realname"] != null)
                {
                    si.Author = HttpContext.Current.Session["realname"].ToString();
                }
                else
                {
                    if (HttpContext.Current.Session["username"] != null)
                    {
                        si.Author = HttpContext.Current.Session["username"].ToString();
                    }
                }                                       //填加xls文件作者信息
                si.ApplicationName = "NPOI";            //填加xls文件创建程序信息
                si.LastAuthor = "OA系统";           //填加xls文件最后保存者信息
                si.Comments = "OA系统自动创建文件";      //填加xls文件作者信息
                si.Title = strHeaderText;               //填加xls文件标题信息
                si.Subject = strHeaderText;              //填加文件主题信息
                si.CreateDateTime = DateTime.Now;
                workbook.SummaryInformation = si;
            }
            #endregion

            ICellStyle dateStyle = workbook.CreateCellStyle();
            IDataFormat format = workbook.CreateDataFormat();
            dateStyle.DataFormat = format.GetFormat("yyyy-mm-dd");

            #region 取得列宽
            int[] arrColWidth = new int[oldColumnNames.Length];
            for (int i = ; i < oldColumnNames.Length; i++)
            {
                arrColWidth[i] = Encoding.GetEncoding().GetBytes(newColumnNames[i]).Length;
            }

            for (int i = ; i < dtSource.Rows.Count; i++)
            {
                for (int j = ; j < oldColumnNames.Length; j++)
                {
                    int intTemp = Encoding.GetEncoding().GetBytes(dtSource.Rows[i][oldColumnNames[j]].ToString()).Length;
                    if (intTemp > arrColWidth[j])
                    {
                        arrColWidth[j] = intTemp;
                    }
                }
            }
            #endregion
            int rowIndex = ;

            foreach (DataRow row in dtSource.Rows)
            {
                #region 新建表，填充表头，填充列头，样式
                if (rowIndex ==  || rowIndex == )
                {
                    if (rowIndex != )
                    {
                        sheet = workbook.CreateSheet(strSheetName + ((int)rowIndex / ).ToString());
                    }

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

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

                        headerRow.GetCell().CellStyle = headStyle;
                        sheet.AddMergedRegion(new NPOI.SS.Util.CellRangeAddress(, , , dtSource.Columns.Count - ));
                    }
                    #endregion

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

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

                        for (int i = ; i < oldColumnNames.Length; i++)
                        {
                            headerRow.CreateCell(i).SetCellValue(newColumnNames[i]);
                            headerRow.GetCell(i).CellStyle = headStyle;
                            //设置列宽
                            sheet.SetColumnWidth(i, (arrColWidth[i] + ) * );
                        }
                    }
                    #endregion

                    rowIndex = ;
                }
                #endregion

                #region 填充内容
                IRow dataRow = sheet.CreateRow(rowIndex);
                for (int i = ; i < oldColumnNames.Length; i++)
                {
                    ICell newCell = dataRow.CreateCell(i);
                    bool hasImage = false;

                    string drValue = row[oldColumnNames[i]].ToString();

                    switch (dtSource.Columns[oldColumnNames[i]].DataType.ToString())
                    {
                        case "System.Guid"://GUID类型
                        case "System.String"://字符串类型
                            newCell.SetCellValue(drValue);
                            break;
                        case "System.DateTime"://日期类型
                            DateTime dateV;
                            DateTime.TryParse(drValue, out dateV);
                            newCell.SetCellValue(dateV);

                            newCell.CellStyle = dateStyle;//格式化显示
                            break;
                        case "System.Boolean"://布尔型
                            bool boolV = false;
                            bool.TryParse(drValue, out boolV);
                            newCell.SetCellValue(boolV);
                            break;
                        case "System.Int16"://整型
                        case "System.Int32":
                        case "System.Int64":
                        case "System.Byte":
                            int intV = ;
                            int.TryParse(drValue, out intV);
                            newCell.SetCellValue(intV);
                            break;
                        case "System.Byte[]"://二进制流
                            int pictureIdx = ;
                            if (row[oldColumnNames[i]] == null || string.IsNullOrEmpty(drValue))
                            {
                                newCell.SetCellValue("");
                                break;
                            }
                            pictureIdx = workbook.AddPicture((byte[])row[oldColumnNames[i]], PictureType.JPEG);
                            HSSFPatriarch patriarch = (HSSFPatriarch)sheet.CreateDrawingPatriarch();
                            HSSFClientAnchor anchor = new HSSFClientAnchor(, , , , i, rowIndex, i + , rowIndex + );
                            //##处理照片位置，【图片左上角为（col, row）第row+1行col+1列，右下角为（ col +1, row +1）第 col +1+1行row +1+1列，第三个参数为宽，第四个参数为高

                            HSSFPicture pict = (HSSFPicture)patriarch.CreatePicture(anchor, pictureIdx);
                            // pict.Resize();//这句话一定不要，这是用图片原始大小来显示

                            hasImage = true;
                            break;
                        case "System.Decimal"://浮点型
                        case "System.Double":
                            double doubV = ;
                            double.TryParse(drValue, out doubV);
                            newCell.SetCellValue(doubV);
                            break;
                        case "System.DBNull"://空值处理
                            newCell.SetCellValue("");
                            break;
                        default:
                            newCell.SetCellValue("");
                            break;
                    }
                    if (hasImage)
                    {
                        dataRow.HeightInPoints = ;
                    }

                }
                #endregion

                rowIndex++;
            }

            using (MemoryStream ms = new MemoryStream())
            {
                workbook.Write(ms);
                ms.Flush();
                ms.Position = ;

                sheet = null;
                workbook = null;
                return ms;
            }
        }

注意填充内容里的switch循环里的 System.Byte[] ，也就是判断图片流并将转换后的图片输出到Excel的方法。