如何在iTextSharp中制作多页页面？

Question

I have single page document made with iTextSharp (A4 size in portrait orientation). Now I copy first page, paste it as second - there are two same pages. In Acrobat Reader there is option to print multiple sheets per page - so I can print those 2 pages on 1 in landscape orientation.

How to achieve the same effect, using only iTextSharp?

Answer 1

Please read the tutorial on how to use iText 7, more specifically Chapter 6: Reusing existing PDF documents

In that chapter, you'll find an example called TheGoldenGateBridge_N_up :

PdfDocument pdf = new PdfDocument(new PdfWriter(dest));
PdfDocument sourcePdf = new PdfDocument(new PdfReader(SRC));
//Original page
PdfPage origPage = sourcePdf.getPage(1);
Rectangle orig = origPage.getPageSize();
PdfFormXObject pageCopy = origPage.copyAsFormXObject(pdf);
//N-up page
PageSize nUpPageSize = PageSize.A4.rotate();
PdfPage page = pdf.addNewPage(nUpPageSize);
PdfCanvas canvas = new PdfCanvas(page);
//Scale page
AffineTransform transformationMatrix = AffineTransform.getScaleInstance(
    nUpPageSize.getWidth() / orig.getWidth() / 2f,
    nUpPageSize.getHeight() / orig.getHeight() / 2f);
canvas.concatMatrix(transformationMatrix);
//Add pages to N-up page
canvas.addXObject(pageCopy, 0, orig.getHeight());
canvas.addXObject(pageCopy, orig.getWidth(), orig.getHeight());
canvas.addXObject(pageCopy, 0, 0);
canvas.addXObject(pageCopy, orig.getWidth(), 0);
// close the documents
pdf.close();
sourcePdf.close();

In this example, we add 4 pages of an existing PDF to one page. The principle is called N-upping in which you replace N by a power of 2. In the example, we do 4-upping; you want 2-upping. Changing the 4-up example into a 2-up example is only a matter of applying some simple Math.

You will also benefit from reading this FAQ entry: How to convert an A4 size PDF to a PDF booklet? If you are still using an old version of iText, you can read the iText 5 version of the FAQ entry .

Note: I see a down-vote and an important comment. Please note that your question is seriously flawed because you don't mention which version of iText you are using (I'm assuming the most recent one), nor do you post any code that shows what you've tried (that's not done on Stack Overflow).