• 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 = 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。

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  • 原文地址:https://www.cnblogs.com/LiuLiangXuan/p/5802078.html
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