Some test text!

Loading...
Guides

PDF imposition in JavaScript

More languages

More languages
Java (Android)
C++
C#
C# (.NET Core)
Go
Java
Kotlin
Obj-C
JS (Node.js)
PHP
Python
Ruby
Swift
C# (UWP)
VB
C# (Xamarin)

Sample JavaScript code for using PDFTron SDK to impose (combine) multiple PDF pages. Page imposition can be used to arrange/order pages prior to printing or for document assembly (assemble a 'master' page from several 'source' pages). It is also possible to write applications that can re-order the pages such that they will display in the correct order when the hard copy pages are compiled and folded correctly. Learn more about our JavaScript PDF Library and PDF Editing & Manipulation Library.

Get Started Samples Download

To run this sample, get started with a free trial of PDFTron SDK.

//---------------------------------------------------------------------------------------
// Copyright (c) 2001-2021 by PDFTron Systems Inc. All Rights Reserved.
// Consult legal.txt regarding legal and license information.
//---------------------------------------------------------------------------------------

//-----------------------------------------------------------------------------------
// The sample illustrates how multiple pages can be combined/imposed 
// using PDFNet. Page imposition can be used to arrange/order pages 
// prior to printing or to assemble a 'master' page from several 'source' 
// pages. Using PDFNet API it is possible to write applications that can 
// re-order the pages such that they will display in the correct order 
// when the hard copy pages are compiled and folded correctly. 
//-----------------------------------------------------------------------------------

const { PDFNet } = require('@pdftron/pdfnet-node');
const PDFTronLicense = require('../LicenseKey/LicenseKey');

((exports) => {
  'use strict';

  exports.runImpositionTest = () => {
    const main = async () => {
      try {
        console.log('-------------------------------------------------');
        console.log('Opening the input pdf...');
        const in_doc = await PDFNet.PDFDoc.createFromFilePath('../TestFiles/newsletter.pdf');
        in_doc.initSecurityHandler();

        // Create a list of pages to import from one PDF document to another.
        const import_pages = [];
        for (let itr = await in_doc.getPageIterator(); await itr.hasNext(); await itr.next()) {
          import_pages.push(await itr.current());
        }

        const new_doc = await PDFNet.PDFDoc.create();
        const imported_pages = await new_doc.importPages(import_pages);

        // Paper dimension for A3 format in points. Because one inch has 
        // 72 points, 11.69 inch 72 = 841.69 points
        const media_box = await PDFNet.Rect.init(0, 0, 1190.88, 841.69);
        const mid_point = await media_box.width() / 2;
        const builder = await PDFNet.ElementBuilder.create();
        const writer = await PDFNet.ElementWriter.create();
        for (let i = 0; i < imported_pages.length; ++i) {
          // Create a blank new A3 page and place on it two pages from the input document.
          const new_page = await new_doc.pageCreate(media_box);
          writer.beginOnPage(new_page);
          // Place the first page
          let src_page = imported_pages[i];
          var element = await builder.createFormFromPage(src_page);

          let sc_x = mid_point / await src_page.getPageWidth();
          let sc_y = await media_box.height() / await src_page.getPageHeight();
          let scale = sc_x < sc_y ? sc_x : sc_y; // min(sc_x, sc_y)
          await element.getGState().then(gstate => gstate.setTransform(scale, 0, 0, scale, 0, 0));
          writer.writePlacedElement(element);

          // Place the second page
          ++i;
          if (i < imported_pages.length) {
            src_page = imported_pages[i];
            element = await builder.createFormFromPage(src_page);
            sc_x = mid_point / await src_page.getPageWidth();
            sc_y = await media_box.height() / await src_page.getPageHeight();
            scale = sc_x < sc_y ? sc_x : sc_y; // min(sc_x, sc_y)
            await element.getGState().then(gstate => gstate.setTransform(scale, 0, 0, scale, mid_point, 0));
            writer.writePlacedElement(element);
          }

          await writer.end();
          new_doc.pagePushBack(new_page);
        }
        await new_doc.save('../TestFiles/Output/newsletter_booklet.pdf', PDFNet.SDFDoc.SaveOptions.e_linearized);
        console.log('Done. Result saved in newsletter_booklet.pdf...');

      } catch (err) {
        console.log(err);
      }
    }
    PDFNet.runWithCleanup(main, PDFTronLicense.Key).catch(function(error) {
      console.log('Error: ' + JSON.stringify(error));
    }).then(function(){ PDFNet.shutdown(); });
  };
  exports.runImpositionTest();
})(exports);
// eslint-disable-next-line spaced-comment
//# sourceURL=ImpositionTest.js