用NOPI将图片二进制流导出到Excel

时间:2021-07-24 19:21:23

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 = 0; i < oldColumnNames.Length; i++)
            {
                arrColWidth[i] = Encoding.GetEncoding(936).GetBytes(newColumnNames[i]).Length;
            }

            for (int i = 0; i < dtSource.Rows.Count; i++)
            {
                for (int j = 0; j < oldColumnNames.Length; j++)
                {
                    int intTemp = Encoding.GetEncoding(936).GetBytes(dtSource.Rows[i][oldColumnNames[j]].ToString()).Length;
                    if (intTemp > arrColWidth[j])
                    {
                        arrColWidth[j] = intTemp;
                    }
                }
            }
            #endregion
            int rowIndex = 0;

            foreach (DataRow row in dtSource.Rows)
            {
                #region 新建表,填充表头,填充列头,样式
                if (rowIndex == 65535 || rowIndex == 0)
                {
                    if (rowIndex != 0)
                    {
                        sheet = workbook.CreateSheet(strSheetName + ((int)rowIndex / 65535).ToString());
                    }

                    #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 NPOI.SS.Util.CellRangeAddress(0, 0, 0, dtSource.Columns.Count - 1));
                    }
                    #endregion


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

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

                        for (int i = 0; i < oldColumnNames.Length; i++)
                        {
                            headerRow.CreateCell(i).SetCellValue(newColumnNames[i]);
                            headerRow.GetCell(i).CellStyle = headStyle;
                            //设置列宽   
                            sheet.SetColumnWidth(i, (arrColWidth[i] + 1) * 256);
                        }
                    }
                    #endregion

                    rowIndex = 2;
                }
                #endregion


                #region 填充内容
                IRow dataRow = sheet.CreateRow(rowIndex);
                for (int i = 0; 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 = 0;
                            int.TryParse(drValue, out intV);
                            newCell.SetCellValue(intV);
                            break;
                        case "System.Byte[]"://二进制流
                            int pictureIdx = 0;
                            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(10, 0, 2, 0, i, rowIndex, i + 1, rowIndex + 1);
                            //##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 = 0;
                            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 = 80;
                    }

                }
                #endregion

                rowIndex++;
            }


            using (MemoryStream ms = new MemoryStream())
            {
                workbook.Write(ms);
                ms.Flush();
                ms.Position = 0;

                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。