Excel文件转为其他格式文件

引用：Spire.XLS 是一个 Excel 文件的读写库，无需安装office，使用起来也挺方便的。Spire还有一些其他的库（Spire.Doc，Spire.Pdf……）

说明：Spire.XLS.dll还会实例化Spire.Pdf.dll中的类，所以Spire.XLS.dll ，Spire.Pdf.dll ，Spire.License.dll 这3个dll一起使用

Excel转图片：

                    //初始化一个Workbook实例，并加载一个工作簿文件 
                    Workbook workbookExcel = new Workbook();
                    workbookExcel.LoadFromFile(paramSourceBookPath);//路径
                    //循环将工作表保存为图片 
                    if (workbookExcel != null)
                    {
                        for (int i = 0; i < workbookExcel.Worksheets.Count; i++)
                        {
                            string pngPath = pngDirectoryName + "\" + (i + 1).ToString() + ".png";
                            Worksheet sheet = workbookExcel.Worksheets[i];
                            sheet.SaveToImage(pngPath);
                            sheet.Clear();
                            Thread.Sleep(100);
                            CaptureImage(pngPath, 0, 50, pngPath);//截取图片，去掉版本信息
                        }
                    }    

试用版的spire.xls在转换时，会在文件中加入一个版本信息：Evaluation Warning : The document wascreated with Spire.XLS for .NET，去掉这个信息，我直接截取图片了

/// <summary>
        /// 截取图片(去掉版本信息：Evaluation Warning : The document wascreated with Spire.XLS for .NET)
        /// </summary>
        /// <param name="fromImagePath"></param>
        /// <param name="offsetX"></param>
        /// <param name="offsetY"></param>
        /// <param name="toImagePath"></param>
        public void CaptureImage(string fromImagePath, int offsetX, int offsetY, string toImagePath)
        {
            //原图片文件
            Image fromImage = Image.FromFile(fromImagePath);
            int width = fromImage.Width;
            int height = fromImage.Height - offsetY;
            //创建新图位图
            Bitmap bitmap = new Bitmap(width, height);
            //创建作图区域
            Graphics graphic = Graphics.FromImage(bitmap);
            //截取原图相应区域写入作图区
            graphic.DrawImage(fromImage, 0, 0, new Rectangle(offsetX, offsetY, width, height), GraphicsUnit.Pixel);
            //从作图区生成新图
            Image saveImage = Image.FromHbitmap(bitmap.GetHbitmap());
            //释放资源   
            graphic.Dispose();
            bitmap.Dispose();
            fromImage.Dispose();
            FileInfo oldImage = new FileInfo(fromImagePath);
            if (oldImage.Exists)
            {
                global::System.IO.File.Delete(fromImagePath);
            }
            //保存图片
            saveImage.Save(toImagePath, System.Drawing.Imaging.ImageFormat.Png);
            //释放资源   
            saveImage.Dispose();
        } 

Excel转其他格式文件：

// 源文件路径  
            string sourceFilePath = OpenFile.FileName;
            SaveFileDialog saveFileDialog = new SaveFileDialog();
            switch (fileFormat)
            {
                case FileFormat.Bitmap:
                    saveFileDialog.Filter = "Bitmap(*.bmp)|*.bmp";
                    break;
                case FileFormat.PDF:
                    saveFileDialog.Filter = "PDF Document(*.pdf)|*.pdf";
                    break;
                case FileFormat.ODS:
                    saveFileDialog.Filter = "OpenOffice Document Spreadsheet(*.ods)|*.ods";
                    break;
                case FileFormat.CSV:
                    saveFileDialog.Filter = "CSV(*.csv)|*.csv";
                    break;
                case FileFormat.XML:
                    saveFileDialog.Filter = "XML(*.xml)|*.xml";
                    break;
                case FileFormat.XPS:
                    saveFileDialog.Filter = "XPS(*.xps)|*.xps";
                    break;
                case FileFormat.Version2007:
                    saveFileDialog.Filter = "XPS(*.xps)|*.xps";
                    break;
                default:
                    break;
            }
            saveFileDialog.FilterIndex = 0;
            if (saveFileDialog.ShowDialog() != DialogResult.OK)
                return;
            // 转换后的目标文件路径  
            string destFilePath = saveFileDialog.FileName;
            // 转换  
            Workbook workbook = new Workbook();
            workbook.LoadFromFile(sourceFilePath);
            workbook.SaveToFile(destFilePath, fileFormat);