Reordering pages

JAVA

/*
    This file is part of the iText (R) project.
    Copyright (c) 1998-2023 Apryse Group NV
    Authors: Apryse Software.

    For more information, please contact iText Software at this address:
    sales@itextpdf.com
 */
package com.itextpdf.samples.sandbox.stamper;

import com.itextpdf.io.source.RandomAccessSourceFactory;
import com.itextpdf.kernel.pdf.PdfDocument;
import com.itextpdf.kernel.pdf.PdfReader;
import com.itextpdf.kernel.pdf.PdfWriter;
import com.itextpdf.kernel.pdf.ReaderProperties;
import com.itextpdf.layout.Document;
import com.itextpdf.layout.element.AreaBreak;
import com.itextpdf.layout.element.Paragraph;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.util.ArrayList;
import java.util.List;

public class ReorderPages {
    public static final String DEST = "./target/sandbox/stamper/reorder_pages.pdf";

    public static void main(String[] args) throws Exception {
        File file = new File(DEST);
        file.getParentFile().mkdirs();

        new ReorderPages().manipulatePdf(DEST);
    }

    protected void manipulatePdf(String dest) throws Exception {
        PdfDocument srcDoc = new PdfDocument(new PdfReader(new RandomAccessSourceFactory()
                .createSource(createBaos().toByteArray()), new ReaderProperties()));

        PdfDocument resultDoc = new PdfDocument(new PdfWriter(dest));

        // One should call this method to preserve the outlines of the source pdf file, otherwise they
        // will be absent in the resultant document to which we copy pages. In this particular sample,
        // however, this line doesn't make sense, since the source pdf lacks outlines
        resultDoc.initializeOutlines();

        List<Integer> pages = new ArrayList<>();
        pages.add(1);
        for (int i = 13; i <= 15; i++) {
            pages.add(i);
        }
        for (int i = 2; i <= 12; i++) {
            pages.add(i);
        }
        pages.add(16);
        srcDoc.copyPagesTo(pages, resultDoc);

        resultDoc.close();
        srcDoc.close();
    }

    // Create a temporary document in memory. Then we will reopen it and change the order of its pages
    private static ByteArrayOutputStream createBaos() {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();

        PdfDocument pdfDoc = new PdfDocument(new PdfWriter(baos));
        Document doc = new Document(pdfDoc);

        for (int i = 1; i < 17; i++) {
            doc.add(new Paragraph(String.format("Page %s", i)));
            if (16 != i) {
                doc.add(new AreaBreak());
            }
        }
        doc.close();

        return baos;
    }
}

C#

using System;
using System.Collections.Generic;
using System.IO;
using iText.IO.Source;
using iText.Kernel.Pdf;
using iText.Layout;
using iText.Layout.Element;

namespace iText.Samples.Sandbox.Stamper 
{
    public class ReorderPages 
    {
        public const String DEST = "results/sandbox/stamper/reorder_pages.pdf";

        public static void Main(String[] args) 
        {
            FileInfo file = new FileInfo(DEST);
            file.Directory.Create();
            
            new ReorderPages().ManipulatePdf(DEST);
        }

        protected void ManipulatePdf(String dest)
        {
            PdfDocument srcDoc = new PdfDocument(new PdfReader(new RandomAccessSourceFactory()
                    .CreateSource(CreateBaos().ToArray()), new ReaderProperties()));
            
            PdfDocument resultDoc = new PdfDocument(new PdfWriter(dest));
            
            // One should call this method to preserve the outlines of the source pdf file, otherwise they
            // will be absent in the resultant document to which we copy pages. In this particular sample,
            // however, this line doesn't make sense, since the source pdf lacks outlines
            resultDoc.InitializeOutlines();
            
            IList<int> pages = new List<int>();
            pages.Add(1);
            for (int i = 13; i <= 15; i++) 
            {
                pages.Add(i);
            }
            for (int i = 2; i <= 12; i++) 
            {
                pages.Add(i);
            }
            pages.Add(16);
            srcDoc.CopyPagesTo(pages, resultDoc);
            
            resultDoc.Close();
            srcDoc.Close();
        }

        // Create a temporary document in memory. Then we will reopen it and change the order of its pages
        private static MemoryStream CreateBaos() 
        {
            MemoryStream baos = new MemoryStream();
            
            PdfDocument pdfDoc = new PdfDocument(new PdfWriter(baos));
            Document doc = new Document(pdfDoc);
            
            for (int i = 1; i < 17; i++) 
            {
                doc.Add(new Paragraph("Page " + i));
                if (16 != i) 
                {
                    doc.Add(new AreaBreak());
                }
            }
            doc.Close();
            
            return baos;
        }
    }
}