1 winform将pdf转图片，有案例，连接为：https://download.csdn.net/download/mingjing941018/20216747

2 Asp.net MVC将pdf转图片

使用Nuget安装包安装Freespire.pdf，控制器中相关代码：

/// <summary>/// 将本地的pdf文件保存为图片/// </summary>/// <param name="pdfName"></param>/// <returns></returns>[HttpPost]public ActionResult GetPdtPic(string folder, string pdfName){try{string bPath = AppDomain.CurrentDomain.SetupInformation.ApplicationBase + "Content\\tjbg";string bFileName = pdfName + ".pdf";string bPdfPath = $"{bPath}\\{folder}\\{bFileName}";//var pdf = PdfDocument.Load(bPdfPath);PdfDocument pdf = new PdfDocument();pdf.LoadFromFile(bPdfPath);var pdfpage = pdf.Pages.Count;//var pagesizes = pdf.PageSizes;for (int i = 1; i <= pdfpage; i++){//Size size = new Size();//size.Height = (int)pagesizes[(i - 1)].Height;//size.Width = (int)pagesizes[(i - 1)].Width;可以把".jpg"写成其他形式//RenderPage(bPdfPath, i, size, bPath + "\\" + i.ToString() + @".jpg", "");Image bImg = pdf.SaveAsImage(i);MemoryStream imgstream = new MemoryStream();bImg.Save(imgstream, ImageFormat.Jpeg);byte[] byData = new Byte[imgstream.Length];imgstream.Position = 0;imgstream.Read(byData, 0, byData.Length);imgstream.Close();//base64 = Convert.ToBase64String(byData);System.Drawing.Image bmp = System.Drawing.Image.FromStream(imgstream);string fileName = string.Format(i.ToString() + @".jpg");bmp.Save(bPath + "\\"+folder+"\\" + fileName, System.Drawing.Imaging.ImageFormat.Jpeg);}pdf.Dispose();return Json(new { Code = 0,Msg = "",Count = pdfpage });}catch (Exception e) {return Json(new { Code = -1,Msg = e.Message,Count = 0 });}}

执行后提示：Spire.PDF Free version is limited to 10 pages of PDF. This limitation is enforced during loading and creating files.When converting PDF to Image, the first 3 pages of PDF files will be converted to Image format successfully。

3 使用magick.net-Q16-AnyCPU进行转换，速度太慢，绝对不能用，网上有资料说这个只能转gif图片，未进行验证

相关代码：

try{string bPath = AppDomain.CurrentDomain.SetupInformation.ApplicationBase + "Content\\tjbg";string bFileName = pdfName + ".pdf";string bPdfPath = $"{bPath}\\{folder}\\{bFileName}";int bCount = 0;MagickReadSettings settings = new MagickReadSettings();settings.Density = new Density(900, 900); //设置质量using (MagickImageCollection images = new MagickImageCollection()){images.Read(bPdfPath, settings);bCount = images.Count;for (int i = 0; i < bCount; i++){MagickImage image = (MagickImage)images[i];image.Format = MagickFormat.Jpeg;string fileName = string.Format(i.ToString() + @".jpg");image.Write(bPath + "\\" + folder + "\\" + fileName);}}return Json(new { Code = 0, Msg = "", Count = bCount });}catch (Exception ex){return Json(new { Code = -1, Msg = ex.Message, Count = 0 });}

4 使用Aspose.PDF.dll进行转换

相关代码：

try{string bPath = AppDomain.CurrentDomain.SetupInformation.ApplicationBase + "Content\\tjbg";string bFileName = pdfName + ".pdf";string bPdfPath = $"{bPath}\\{folder}\\{bFileName}";Document pdfDocument = new Document(bPdfPath);int bCount = pdfDocument.Pages.Count;for (int pageCount = 1; pageCount <= bCount; pageCount++){string fileName = string.Format(pageCount.ToString() + @".jpg");using (FileStream imageStream = new FileStream(bPath + "\\" + folder + "\\" + fileName, FileMode.Create)){// Create PNG device with specified attributes// Width, Height, Resolution, Quality// Quality [0-100], 100 is Maximum// Create Resolution objectResolution resolution = new Resolution(300);PngDevice pngDevice = new PngDevice(resolution);// Convert a particular page and save the image to streampngDevice.Process(pdfDocument.Pages[pageCount], imageStream);// Close streamimageStream.Close();}}return Json(new { Code = 0, Msg = "", Count = bCount });}catch (Exception ex){return Json(new { Code = -1, Msg = ex.Message, Count = 0 });}

执行后提示：At most 4 elements (for any collection) can be viewed in evaluation mode