Develop Reference

ABCpdf only rendering first page

When I try to save each page as GIF using ABCpdf, only the first page is saved.
For example: I have a PDF that has 3 pages. I use ABCpdf to render each page to a stream, which is saved to disk. When I open the files in my destination folder, all 3 files show the first page content.
Here's my code:
using (Doc theDoc = new Doc())
{
XReadOptions options = new XReadOptions { ReadModule = ReadModuleType.Pdf };
theDoc.Read(inputbytearray, options);
using (MemoryStream ms = new MemoryStream())
{
theDoc.Rendering.DotsPerInch = 150;
int n = theDoc.PageCount;
for (int i = 1; i <= n; i++)
{
Guid FileName = Guid.NewGuid();
theDoc.Rect.String = theDoc.CropBox.String;
theDoc.Rendering.SaveAppend = (i != 1);
theDoc.Rendering.SaveCompression = XRendering.Compression.G4;
theDoc.PageNumber = i;
theDoc.Rendering.Save(string.Format("{0}.gif", FileName), ms);
using (var streamupload = new MemoryStream(ms.GetBuffer(), writable: false))
{
_BlobStorageService.UploadfromStream(FileName.ToString(), streamupload, STR_Gif, STR_Imagegif);
}
}
// theDoc.Clear();
}
}

The Rendering.SaveAppend property is only applicable when saving TIFF images. For GIFs you would need to save a separate image for each PDF page.
private void button1_Click(object sender, System.EventArgs e)
{
string theDir = Directory.GetParent(Directory.GetCurrentDirectory()).Parent.FullName + #"\files\";
// Create test PDF
using (Doc doc = new Doc())
{
for (int i = 1; i <= 3; i++)
{
doc.Page = doc.AddPage();
doc.AddHtml("<font size=24>PAGE " + i.ToString());
}
doc.Save(Path.Combine(theDir, "test.pdf"));
}
// Save PDF pages to GIF streams
using (Doc doc = new Doc())
{
doc.Read(Path.Combine(theDir, "test.pdf"));
for (int i = 1; i <= doc.PageCount; i++)
{
doc.PageNumber = i;
doc.Rect.String = doc.CropBox.String;
using (MemoryStream ms = new MemoryStream())
{
doc.Rendering.Save("dummy.gif", ms);
using (FileStream fs = File.Create(Path.Combine(theDir, "p" + i.ToString() + ".gif")))
{
ms.Seek(0, SeekOrigin.Begin);
ms.CopyTo(fs);
}
}
}
}
}

Adding a Table into the Footer of a PDF

After creating a PDF from HTML, I need to add a Footer to each page. The Footer is going to be a single-row, three-column table, with the left cell being an external reference ID, the center being a "Page X of Y", and the right being a date stamp. I have no experience with iTextSharp, but after reading various posts I created the following PageEventHandler
UPDATED CODE
public class FooterEvent : PdfPageEventHelper
{
PdfContentByte cb;
#region Properties
private string _FooterLeft;
public string FooterLeft
{
get { return _FooterLeft; }
set { _FooterLeft = value; }
}
private string _FooterCenter;
public string FooterCenter
{
get { return _FooterCenter; }
set { _FooterCenter = value; }
}
private string _FooterRight;
public string FooterRight
{
get { return _FooterRight; }
set { _FooterRight = value; }
}
private Font _FooterFont;
public Font FooterFont
{
get { return _FooterFont; }
set { _FooterFont = value; }
}
#endregion
public override void OnEndPage(PdfWriter writer, Document document)
{
base.OnEndPage(writer, document);
Font font = new Font(Font.FontFamily.HELVETICA, 12, Font.NORMAL, BaseColor.BLACK);
PdfPTable FooterTable = new PdfPTable(3);
FooterTable.TotalWidth = document.PageSize.Width - document.LeftMargin - document.RightMargin;
PdfPCell FooterLeftCell = new PdfPCell(new Phrase(2, FooterLeft, FooterFont));
FooterLeftCell.HorizontalAlignment = Element.ALIGN_LEFT;
FooterLeftCell.VerticalAlignment = Element.ALIGN_CENTER;
FooterLeftCell.Border = 0;
FooterTable.AddCell(FooterLeftCell);
PdfPCell FooterCenterCell = new PdfPCell(new Phrase(2, FooterCenter, FooterFont));
FooterCenterCell.HorizontalAlignment = Element.ALIGN_CENTER;
FooterCenterCell.VerticalAlignment = Element.ALIGN_CENTER;
FooterCenterCell.Border = 0;
FooterTable.AddCell(FooterCenterCell);
PdfPCell FooterRightCell = new PdfPCell(new Phrase(2, FooterRight, FooterFont));
FooterRightCell.HorizontalAlignment = Element.ALIGN_RIGHT;
FooterRightCell.VerticalAlignment = Element.ALIGN_CENTER;
FooterRightCell.Border = 0;
FooterTable.AddCell(FooterRightCell);
FooterTable.WriteSelectedRows(0, -1, document.LeftMargin, document.BottomMargin, cb);
}
}
ADDED RESPONSE
After editing my PageEvent, I'm still having issues. It's come to mind that I'm probably having issues with calling the PageEvent and adding it to the PDF (no experience with iTextSharp). Below is my attempt to add the Footer to an existing PDF that has been passed as byte[].
byte[] output = null;
string identifier = id;
string time = DateTime.Now.ToString();
string page = null;
PdfReader reader = new PdfReader(original);
int n = reader.NumberOfPages;
try
{
using (MemoryStream ms = new MemoryStream())
{
using (Document doc = new Document(PageSize.LETTER, 100, 100, 100, 100))
{
using (PdfWriter writer = PdfWriter.GetInstance(doc, ms))
{
FooterEvent footer = new FooterEvent();
writer.PageEvent = footer;
footer.FooterFont = FontFactory.GetFont(BaseFont.HELVETICA, 12, BaseColor.BLACK);
doc.Open();
for (int i = 1; i < n + 1; ++i)
{
doc.NewPage();
page = "Page " + i + " of " + n;
footer.FooterLeft = identifier;
footer.FooterCenter = page;
footer.FooterRight = time;
doc.Add(new Paragraph(reader.GetPageContent(i).ToString()));
//Probably wrong. Trying to add contents from each page in original PDF
}
doc.Close();
}
}
output = ms.ToArray();
}
}
catch (Exception ex)
{
//Some Message added later
}
return output;
Any help is appreciated. Thanks in advance.

Try this, its working for me:
FooterTable.WriteSelectedRows(0, -1, document.LeftMargin, FooterTable.TotalHeight, cb);
Check this post
Header, footer and large tables with iTextSharp

You wrote:
FooterTable.WriteSelectedRows(0, 0, document.LeftMargin, document.RightMargin, cb);
However, the method is:
FooterTable.WriteSelectedRows(rowStart, rowEnd, x, y, cb);
Which means that you're asking to write a selection of rows starting with row 0 and ending with row 0, or: you're asking to write not a single row.
Moreover, you provide an x value instead of a y value. Change that line into:
FooterTable.WriteSelectedRows(0, -1, document.LeftMargin, document.BottomMargin, cb);

Memory error joining pdf files

I'm building a program in C# that reads 3 PDF files, performs some sorting based on the user ID and generates an output PDF file.
It currently generates 1254 pdf files(approx 5 MB each) and when I try to join them, throws an Out Of Memmory Exception .
How can I join these files, considering that it results in a 4 GB file size?
The following code joins all PDF files into a single output file.
public void CombineMultiplePDFs(string[] fileNames, string outFile)
{
int pageOffset = 0;
ArrayList master = new ArrayList();
int f = 0;
Document document = null;
PdfCopy writer = null;
while (f < fileNames.Length)
{
// we create a reader for a certain document
PdfReader reader = new PdfReader(fileNames[f]);
reader.ConsolidateNamedDestinations();
// we avisorieve the total number of pages
int n = reader.NumberOfPages;
pageOffset += n;
if (f == 0)
{
// step 1: creation of a document-object
document = new Document(reader.GetPageSizeWithRotation(1));
// step 2: we create a writer that listens to the document
writer = new PdfCopy(document, new FileStream(outFile, FileMode.Create));
// step 3: we open the document
document.Open();
}
// step 4: we add content
for (int i = 0; i < n; )
{
++i;
if (writer != null)
{
PdfImportedPage page = writer.GetImportedPage(reader, i);
writer.AddPage(page);
}
}
PRAcroForm form = reader.AcroForm;
if (form != null && writer != null)
{
writer.CopyAcroForm(reader);
}
f++;
}
// step 5: we close the document
if (document != null)
{
document.Close();
}
}

itextsharp trimming pdf document's pages

I have a pdf document that has form fields that I'm filling out programatically with c#. Depending on three conditions, I need to trim (delete) some of the pages from that document.
Is that possible to do?
for condition 1: I need to keep pages 1-4 but delete pages 5 and 6
for condition 2: I need to keep pages 1-4 but delete 5 and keep 6
for condition 3: I need to keep pages 1-5 but delete 6

Use PdfReader.SelectPages() combined with PdfStamper. The code below uses iTextSharp 5.5.1.
public void SelectPages(string inputPdf, string pageSelection, string outputPdf)
{
using (PdfReader reader = new PdfReader(inputPdf))
{
reader.SelectPages(pageSelection);
using (PdfStamper stamper = new PdfStamper(reader, File.Create(outputPdf)))
{
stamper.Close();
}
}
}
Then you call this method with the correct page selection for each condition.
Condition 1:
SelectPages(inputPdf, "1-4", outputPdf);
Condition 2:
SelectPages(inputPdf, "1-4,6", outputPdf);
or
SelectPages(inputPdf, "1-6,!5", outputPdf);
Condition 3:
SelectPages(inputPdf, "1-5", outputPdf);
Here's the comment from the iTextSharp source code on what makes up a page selection. This is in the SequenceList class which is used to process a page selection:
/**
* This class expands a string into a list of numbers. The main use is to select a
* range of pages.
* <p>
* The general systax is:<br>
* [!][o][odd][e][even]start-end
* <p>
* You can have multiple ranges separated by commas ','. The '!' modifier removes the
* range from what is already selected. The range changes are incremental, that is,
* numbers are added or deleted as the range appears. The start or the end, but not both, can be ommited.
*/

Instead of deleting pages in a document what you actually do is create a new document and only import the pages that you want to keep. Below is a full working WinForms app that does that (targetting iTextSharp 5.1.1.0). The last parameter to the function removePagesFromPdf is an array of pages to keep.
The code below works off of physical files but would be very easy to convert to something based on streams so that you don't have to write to disk if you don't want to.
using System;
using System.ComponentModel;
using System.IO;
using System.Linq;
using System.Windows.Forms;
using iTextSharp.text.pdf;
using iTextSharp.text;
namespace Full_Profile1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
//The files that we are working with
string sourceFolder = Environment.GetFolderPath(Environment.SpecialFolder.Desktop);
string sourceFile = Path.Combine(sourceFolder, "Test.pdf");
string destFile = Path.Combine(sourceFolder, "TestOutput.pdf");
//Remove all pages except 1,2,3,4 and 6
removePagesFromPdf(sourceFile, destFile, 1, 2, 3, 4, 6);
this.Close();
}
public void removePagesFromPdf(String sourceFile, String destinationFile, params int[] pagesToKeep)
{
//Used to pull individual pages from our source
PdfReader r = new PdfReader(sourceFile);
//Create our destination file
using (FileStream fs = new FileStream(destinationFile, FileMode.Create, FileAccess.Write, FileShare.None))
{
using (Document doc = new Document())
{
using (PdfWriter w = PdfWriter.GetInstance(doc, fs))
{
//Open the desitination for writing
doc.Open();
//Loop through each page that we want to keep
foreach (int page in pagesToKeep)
{
//Add a new blank page to destination document
doc.NewPage();
//Extract the given page from our reader and add it directly to the destination PDF
w.DirectContent.AddTemplate(w.GetImportedPage(r, page), 0, 0);
}
//Close our document
doc.Close();
}
}
}
}
}
}

Here is the code I use to copy all but the last page of an existing PDF. Everything is in memory streams. The variable pdfByteArray is a byte[] of the original pdf obtained using ms.ToArray(). pdfByteArray is overwritten with the new PDF.
PdfReader originalPDFReader = new PdfReader(pdfByteArray);
using (MemoryStream msCopy = new MemoryStream())
{
using (Document docCopy = new Document())
{
using (PdfCopy copy = new PdfCopy(docCopy, msCopy))
{
docCopy.Open();
for (int pageNum = 1; pageNum <= originalPDFReader.NumberOfPages - 1; pageNum ++)
{
copy.AddPage(copy.GetImportedPage(originalPDFReader, pageNum ));
}
docCopy.Close();
}
}
pdfByteArray = msCopy.ToArray();

I know it's an old post, Simply I extend the #chris-haas solution to the next level.
Delete the selected pages after that save them into the separate pdf file.
//ms is MemoryStream and fs is FileStream
ms.CopyTo(fs);
Save the Stream to a separate pdf file. 100% working without any error.
pageRange="5"
pageRange="2,15-20"
pageRange="1-5,15-20"
You can pass the pageRange vales like the above-given samples.
private void DeletePagesNew(string pageRange, string SourcePdfPath, string OutputPdfPath, string Password = "")
{
try
{
var pagesToDelete = new List<int>();
if (pageRange.IndexOf(",") != -1)
{
var tmpHold = pageRange.Split(',');
foreach (string nonconseq in tmpHold)
{
if (nonconseq.IndexOf("-") != -1)
{
var rangeHold = nonconseq.Split('-');
for (int i = Convert.ToInt32(rangeHold[0]), loopTo = Convert.ToInt32(rangeHold[1]); i <= loopTo; i++)
pagesToDelete.Add(i);
}
else
{
pagesToDelete.Add(Convert.ToInt32(nonconseq));
}
}
}
else if (pageRange.IndexOf("-") != -1)
{
var rangeHold = pageRange.Split('-');
for (int i = Convert.ToInt32(rangeHold[0]), loopTo1 = Convert.ToInt32(rangeHold[1]); i <= loopTo1; i++)
pagesToDelete.Add(i);
}
else
{
pagesToDelete.Add(Convert.ToInt32(pageRange));
}
var Reader = new PdfReader(SourcePdfPath);
int[] pagesToKeep;
pagesToKeep = Enumerable.Range(1, Reader.NumberOfPages).ToArray();
using (var ms = new MemoryStream())
{
using (var fs = new FileStream(OutputPdfPath, FileMode.Create, FileAccess.Write, FileShare.None))
{
using (var doc = new Document())
{
using (PdfWriter w = PdfWriter.GetInstance(doc, fs))
{
doc.Open();
foreach (int p in pagesToKeep)
{
if (pagesToDelete.FindIndex(s => s == p) != -1)
{
continue;
}
// doc.NewPage()
// w.DirectContent.AddTemplate(w.GetImportedPage(Reader, p), 0, 0)
//
doc.SetPageSize(Reader.GetPageSize(p));
doc.NewPage();
PdfContentByte cb = w.DirectContent;
PdfImportedPage pageImport = w.GetImportedPage(Reader, p);
int rot = Reader.GetPageRotation(p);
if (rot == 90 || rot == 270)
{
cb.AddTemplate(pageImport, 0, -1.0f, 1.0f, 0, 0, Reader.GetPageSizeWithRotation(p).Height);
}
else
{
cb.AddTemplate(pageImport, 1.0f, 0, 0, 1.0f, 0, 0);
}
cb = default;
pageImport = default;
rot = default;
}
ms.CopyTo(fs);
fs.Flush();
doc.Close();
}
}
}
}
pagesToDelete = null;
Reader.Close();
Reader = default;
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}

split PDF into multiple files in C#

We have a C# Windows service that currently processes all the PDFs by reading the 2D barcode on the PDF using a 3rd party component and then updates the database and stores the document in the Document repository.
Is there a way I can cut the files after reading the barcode and store it as another document?
For example if there is a 10 page document, it should split into 10 different files.
Thanks.

I met the same question, you can use itextsharp component tools to split the document
public Split(String[] args)
{
if (args.Length != 4)
{
Console.Error.WriteLine("This tools needs 4 parameters:\njava Split srcfile destfile1 destfile2 pagenumber");
}
else
{
try
{
int pagenumber = int.Parse(args[3]);
// we create a reader for a certain document
PdfReader reader = new PdfReader(args[0]);
// we retrieve the total number of pages
int n = reader.NumberOfPages;
Console.WriteLine("There are " + n + " pages in the original file.");
if (pagenumber < 2 || pagenumber > n)
{
throw new DocumentException("You can't split this document at page " + pagenumber + "; there is no such page.");
}
// step 1: creation of a document-object
Document document1 = new Document(reader.GetPageSizeWithRotation(1));
Document document2 = new Document(reader.GetPageSizeWithRotation(pagenumber));
// step 2: we create a writer that listens to the document
PdfWriter writer1 = PdfWriter.GetInstance(document1, new FileStream(args[1], FileMode.Create));
PdfWriter writer2 = PdfWriter.GetInstance(document2, new FileStream(args[2], FileMode.Create));
// step 3: we open the document
document1.Open();
PdfContentByte cb1 = writer1.DirectContent;
document2.Open();
PdfContentByte cb2 = writer2.DirectContent;
PdfImportedPage page;
int rotation;
int i = 0;
// step 4: we add content
while (i < pagenumber - 1)
{
i++;
document1.SetPageSize(reader.GetPageSizeWithRotation(i));
document1.NewPage();
page = writer1.GetImportedPage(reader, i);
rotation = reader.GetPageRotation(i);
if (rotation == 90 || rotation == 270)
{
cb1.AddTemplate(page, 0, -1f, 1f, 0, 0, reader.GetPageSizeWithRotation(i).Height);
}
else
{
cb1.AddTemplate(page, 1f, 0, 0, 1f, 0, 0);
}
}
while (i < n)
{
i++;
document2.SetPageSize(reader.GetPageSizeWithRotation(i));
document2.NewPage();
page = writer2.GetImportedPage(reader, i);
rotation = reader.GetPageRotation(i);
if (rotation == 90 || rotation == 270)
{
cb2.AddTemplate(page, 0, -1f, 1f, 0, 0, reader.GetPageSizeWithRotation(i).Height);
}
else
{
cb2.AddTemplate(page, 1f, 0, 0, 1f, 0, 0);
}
Console.WriteLine("Processed page " + i);
}
// step 5: we close the document
document1.Close();
document2.Close();
}
catch(Exception e)
{
Console.Error.WriteLine(e.Message);
Console.Error.WriteLine(e.StackTrace);
}
}
}

You can use a PDF library like PDFSharp, read the file, iterate through each of the pages, add them to a new PDF document and save them on the filesystem. You can then also delete or keep the original.
It's quite a bit of code, but very simple and these samples should get you started.
http://www.pdfsharp.net/wiki/Default.aspx?Page=ConcatenateDocuments-sample&NS=&AspxAutoDetectCookieSupport=1

A previous question answers your partially - how to split pdf documents, if you know where the barcodes are then you can split the documents easily:
How can I split up a PDF file into pages (preferably C#)
The recommendation is a library called PDFSharp and a sample demonstrating PDF splitting.

public int ExtractPages(string sourcePdfPath, string DestinationFolder)
{
int p = 0;
try
{
iTextSharp.text.Document document;
iTextSharp.text.pdf.PdfReader reader = new iTextSharp.text.pdf.PdfReader(new iTextSharp.text.pdf.RandomAccessFileOrArray(sourcePdfPath), new ASCIIEncoding().GetBytes(""));
if (!Directory.Exists(sourcePdfPath.ToLower().Replace(".pdf", "")))
{
Directory.CreateDirectory(sourcePdfPath.ToLower().Replace(".pdf", ""));
}
else
{
Directory.Delete(sourcePdfPath.ToLower().Replace(".pdf", ""), true);
Directory.CreateDirectory(sourcePdfPath.ToLower().Replace(".pdf", ""));
}
for (p = 1; p <= reader.NumberOfPages; p++)
{
using (MemoryStream memoryStream = new MemoryStream())
{
document = new iTextSharp.text.Document();
iTextSharp.text.pdf.PdfWriter writer = iTextSharp.text.pdf.PdfWriter.GetInstance(document, memoryStream);
writer.SetPdfVersion(iTextSharp.text.pdf.PdfWriter.PDF_VERSION_1_2);
writer.CompressionLevel = iTextSharp.text.pdf.PdfStream.BEST_COMPRESSION;
writer.SetFullCompression();
document.SetPageSize(reader.GetPageSize(p));
document.NewPage();
document.Open();
document.AddDocListener(writer);
iTextSharp.text.pdf.PdfContentByte cb = writer.DirectContent;
iTextSharp.text.pdf.PdfImportedPage pageImport = writer.GetImportedPage(reader, p);
int rot = reader.GetPageRotation(p);
if (rot == 90 || rot == 270)
{
cb.AddTemplate(pageImport, 0, -1.0F, 1.0F, 0, 0, reader.GetPageSizeWithRotation(p).Height);
}
else
{
cb.AddTemplate(pageImport, 1.0F, 0, 0, 1.0F, 0, 0);
}
document.Close();
document.Dispose();
File.WriteAllBytes(DestinationFolder + "/" + p + ".pdf", memoryStream.ToArray());
}
}
reader.Close();
reader.Dispose();
}
catch
{
}
finally
{
GC.Collect();
}
return p - 1;
}
call this function where ever you want and pass the source and destination folder path

This code is based on the PDFsharp library
http://www.pdfsharp.com/PDFsharp/
If you want to split by Book Mark then here is the code.
public static void SplitPDFByBookMark(string fileName)
{
string sInFile = fileName;
PdfReader pdfReader = new PdfReader(sInFile);
try
{
IList<Dictionary<string, object>> bookmarks = SimpleBookmark.GetBookmark(pdfReader);
for (int i = 0; i < bookmarks.Count; ++i)
{
IDictionary<string, object> BM = (IDictionary<string, object>)bookmarks[0];
IDictionary<string, object> nextBM = i == bookmarks.Count - 1 ? null : bookmarks[i + 1];
string startPage = BM["Page"].ToString().Split(' ')[0].ToString();
string startPageNextBM = nextBM == null ? "" + (pdfReader.NumberOfPages + 1) : nextBM["Page"].ToString().Split(' ')[0].ToString();
SplitByBookmark(pdfReader, int.Parse(startPage), int.Parse(startPageNextBM), bookmarks[i].Values.ToArray().GetValue(0).ToString() + ".pdf", fileName);
}
}
catch (Exception ex)
{
throw ex;
}
}
private static void SplitByBookmark(PdfReader reader, int pageFrom, int PageTo, string outPutName, string inPutFileName)
{
Document document = new Document();
FileStream fs = new System.IO.FileStream(System.IO.Path.GetDirectoryName(inPutFileName) + '\\' + outPutName, System.IO.FileMode.Create);
try
{
PdfWriter writer = PdfWriter.GetInstance(document, fs);
document.Open();
PdfContentByte cb = writer.DirectContent;
//holds pdf data
PdfImportedPage page;
if (pageFrom == PageTo && pageFrom == 1)
{
document.NewPage();
page = writer.GetImportedPage(reader, pageFrom);
cb.AddTemplate(page, 0, 0);
pageFrom++;
fs.Flush();
document.Close();
fs.Close();
}
else
{
while (pageFrom < PageTo)
{
document.NewPage();
page = writer.GetImportedPage(reader, pageFrom);
cb.AddTemplate(page, 0, 0);
pageFrom++;
fs.Flush();
document.Close();
fs.Close();
}
}
}
catch (Exception ex)
{
throw ex;
}
finally
{
if (document.IsOpen())
document.Close();
if (fs != null)
fs.Close();
}
}

public void SplitPDFByBookMark(string fileName)
{
string sInFile = fileName;
var pdfReader = new PdfReader(sInFile);
try
{
IList<Dictionary<string, object>> bookmarks = SimpleBookmark.GetBookmark(pdfReader);
for (int i = 0; i < bookmarks.Count; ++i)
{
IDictionary<string, object> BM = (IDictionary<string, object>)bookmarks[i];
IDictionary<string, object> nextBM = i == bookmarks.Count - 1 ? null : bookmarks[i + 1];
string startPage = BM["Page"].ToString().Split(' ')[0].ToString();
string startPageNextBM = nextBM == null ? "" + (pdfReader.NumberOfPages + 1) : nextBM["Page"].ToString().Split(' ')[0].ToString();
SplitByBookmark(pdfReader, int.Parse(startPage), int.Parse(startPageNextBM), bookmarks[i].Values.ToArray().GetValue(0).ToString() + ".pdf", fileName);
}
}
catch (Exception ex)
{
throw ex;
}
}
private void SplitByBookmark(PdfReader reader, int pageFrom, int PageTo, string outPutName, string inPutFileName)
{
Document document = new Document();
using (var fs = new FileStream(Path.GetDirectoryName(inPutFileName) + '\\' + outPutName, System.IO.FileMode.Create))
{
try
{
using (var writer = PdfWriter.GetInstance(document, fs))
{
document.Open();
PdfContentByte cb = writer.DirectContent;
//holds pdf data
PdfImportedPage page;
if (pageFrom == PageTo && pageFrom == 1)
{
document.NewPage();
page = writer.GetImportedPage(reader, pageFrom);
cb.AddTemplate(page, 0, 0);
pageFrom++;
fs.Flush();
document.Close();
fs.Close();
}
else
{
while (pageFrom < PageTo)
{
document.NewPage();
page = writer.GetImportedPage(reader, pageFrom);
cb.AddTemplate(page, 0, 0);
pageFrom++;
fs.Flush();
document.Close();
fs.Close();
}
}
}
//PdfWriter writer = PdfWriter.GetInstance(document, fs);
}
catch (Exception ex)
{
throw ex;
}
}
}
You can install itextsharp from nuget and copy and paste this code in a c# app Call the SplitPDFByBookMark() method and pass the pdf filename.
This code is going to search for you bookmarks and done!

An easy way , using Spire PDF :
using Spire.Pdf;
namespace split_pdf
{
class Program
{
static void Main(string[] args)
{
//open an existing pdf document
PdfDocument doc = new PdfDocument(#"..\Sample3.pdf");
//Split one PDF document to multiple files
String pattern = "SplitDocument-{0}.pdf";
doc.Split(pattern);
String lastPageFileName
= String.Format(pattern, doc.Pages.Count - 1);
doc.Close();
}
}
}
here the Documentation Page : SpirePdf