C# - Pdf rotate using iTextSharp

In C#, with opensource iTextSharp can be find in nuget package, we can easily rotate each pdf pages and save as new file, use below code

using iTextSharp.text;

using iTextSharp.text.pdf;

using System.IO;

namespace PdfRotate

{

    class Program

    {

        static void Main(string[] args)

        {

            //INFO: Change input and ouput path here

            string pdfFilePath = @"C:\Files\sample.pdf";

            string outputPath = @" C:\Files\sampleoutput.pdf ";

            //INFO: Change rotate degree here to 90, 180 etc

            RotatePages(pdfFilePath, outputPath, 180);           

        }

        private static void RotatePages(string pdfFilePath, string outputPath, int rotateDegree)

        {

            PdfReader reader = new PdfReader(pdfFilePath);

            int pagesCount = reader.NumberOfPages;

            for (int n = 1; n <= pagesCount; n++)

            {

                PdfDictionary page = reader.GetPageN(n);

                PdfNumber rotate = page.GetAsNumber(PdfName.ROTATE);

                int rotation =

                        rotate == null ? rotateDegree : (rotate.IntValue + rotateDegree) % 360;

                page.Put(PdfName.ROTATE, new PdfNumber(rotation));

            }

            PdfStamper stamper = new PdfStamper(reader, new FileStream(outputPath, FileMode.Create));

            stamper.Close();

            reader.Close();

        }

    }

}