C# 多个PDF文档合并，带增加书签，两个A4合并到一页A3上

此处用到的库是Itextsharp

/// <summary>
/// 合成pdf文件
/// </summary>
/// <param name="pdffileList"></param>
/// <param name="outMergeFile"></param>
/// <param name="RemovedOldFile"></param>
public static void MergePdfFiles(this List<string> pdffileList, string outMergeFile, bool RemovedOldFile = true)
{byte[] bytes1;using (var fs1 = new FileStream(pdffileList[0], FileMode.Open)) //此处将内容从文本提取至文件流中的目的是避免文件被占用,无法删除{bytes1 = new byte[(int)fs1.Length];var read = fs1.Read(bytes1, 0, bytes1.Length);fs1.Close();}var reader = new PdfReader(bytes1);reader.GetPageSize(1);var rec = reader.GetPageSize(1);     // iTextSharp.text.Rectangle rec = new iTextSharp.text.Rectangle(1000,800);//设置样式var width = rec.Width; var height = rec.Height;using (var document = new iTextSharp.text.Document(rec, 50, 50, 50, 50)) //创建一个文档变量{var pdfWrite = PdfWriter.GetInstance(document, new FileStream(outMergeFile, FileMode.Create));   //创建该文档document.Open();     //打开文档var contentByte = pdfWrite.DirectContent;    //添加内容var testData = new List<Dictionary<string, object>>();var page = 1;for (var i = 0; i < pdffileList.Count; i++){//File.Delete(fileList[i]);byte[] bytes;using (var fs = new FileStream(pdffileList[i], FileMode.Open)){bytes = new byte[(int)fs.Length];var read = fs.Read(bytes, 0, bytes.Length);fs.Close();}reader = new PdfReader(bytes);var pageNum = reader.NumberOfPages;//获取文档页数for (var j = 1; j <= pageNum; j++){document.NewPage();var newPage = pdfWrite.GetImportedPage(reader, j);contentByte.AddTemplate(newPage, 0, 0);var test = new Dictionary<string, object>{{ "Action", "GoTo"}, { "Title", Path.GetFileNameWithoutExtension(pdffileList[i])+"-Sht."+j }, {"Page", $"{page} XYZ 0 0 0 " }};testData.Add(test);page++;}if (RemovedOldFile) File.Delete(pdffileList[i]);}pdfWrite.Outlines = testData;document.Close();}
}

此处使用的库是pdfsharp

  /// <summary>/// /// </summary>/// <param name="fnOri"></param>/// <param name="fnCombine"></param>/// <returns></returns>public static bool CombineA4ToA3(string fnOri, string fnCombine){var fnNew = Path.Combine(Path.GetTempPath(), Path.GetFileName(fnOri));using (var xf = PdfReader.Open(fnOri)){for (var i = xf.PageCount - 1; i >= 0; i--){var curPage = xf.Pages[i];var min = Math.Min(curPage.Width.Millimeter, curPage.Height.Millimeter);var max = Math.Max(curPage.Width.Millimeter, curPage.Height.Millimeter);if (Math.Abs(min - 210) < 3 && Math.Abs(max - 297.0) < 3){if (curPage.Width > curPage.Height) continue;if (curPage.Rotate == 0)curPage.Rotate = 90;else curPage.Rotate = curPage.Rotate % 90 == 0 ? 0 : 90;}else{xf.Pages.Remove(curPage);Console.WriteLine($"第{i + 1} 不是A4.....正在从合并中剔除....");}}if (xf.PageCount > 0){xf.Save(fnNew);xf.Close();}else return false;}//Create the output documentvar outputDocument = new PdfDocument();// Show single pages// (Note: one page contains two pages from the source document)outputDocument.PageLayout = PdfPageLayout.SinglePage;var font = new XFont("Arial", 12, XFontStyleEx.Bold);var format = new XStringFormat{Alignment = XStringAlignment.Center,LineAlignment = XLineAlignment.Far};// Open the external document as XPdfForm objectusing (var form = XPdfForm.FromFile(fnNew)){for (var idx = 0; idx < form.PageCount; idx += 2){// Add a new page to the output documentvar page = outputDocument.AddPage();page.Orientation = PageOrientation.Portrait;page.Size = PageSize.A3;double width = page.Width;double height = page.Height;var gfx = XGraphics.FromPdfPage(page);// Set page number (which is one-based)form.PageNumber = idx + 1;var pn = (idx + 1).ToString();var box = new XRect(0, 0, width, height / 2);// Draw the page identified by the page number like an imagegfx.DrawImage(form, box);// Write document file name and page number on each pagebox.Inflate(0, -10);// gfx.DrawString($"- {idx + 1} -", font, XBrushes.Red, box, format);if (idx + 1 >= form.PageCount) continue;// Set page number (which is one-based)form.PageNumber = idx + 2;var pn1=(idx + 2).ToString();box = new XRect(0, height / 2, width, height / 2);// Draw the page identified by the page number like an imagegfx.DrawImage(form, box);// Write document file name and page number on each pagebox.Inflate(0, -10);//gfx.DrawString($"- {idx + 2} -", font, XBrushes.Red, box, format);var bm=outputDocument.Outlines.Add(Path.GetFileNameWithoutExtension(fnCombine) + $"-SHT-{pn}", page, true, PdfOutlineStyle.Regular,XColor.FromKnownColor(XKnownColor.Black));bm.PageDestinationType = PdfPageDestinationType.FitBH;bm.Top = 0;bm.Left = 0;var bm1 = outputDocument.Outlines.Add(Path.GetFileNameWithoutExtension(fnCombine) + $"-SHT-{pn1}", page, true, PdfOutlineStyle.Regular,XColor.FromKnownColor(XKnownColor.Black));bm1.PageDestinationType = PdfPageDestinationType.FitBH;bm1.Top = height / 2;bm1.Left = 0;}}outputDocument.Save(fnCombine);File.Delete(fnNew);return true;}