How to change the PDF page orientation in PDF viewer

/// <summary>
/// Handles the page orientation changed functionality
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
void LandScapeCB_CheckedChanged(object sender, System.EventArgs e)
        {
            //create a new document
            PdfDocument document = new PdfDocument();
            if (!IsOrientationChanged)
            {
                document = ChangeOrientation(document, IsOrientationChanged);
                IsOrientationChanged = true;
            }
            else
            {
                document = ChangeOrientation(document, IsOrientationChanged);
                IsOrientationChanged = false;
            }
            //saving the orientation changed document in stream
            Stream stream = new MemoryStream();
            document.Save(stream);
            //recreate the loaded document by using orientation changed document
            loadedDocument = new PdfLoadedDocument(stream);
 
            //reload the document in pdfviewer
            pdfViewerControl.Load(loadedDocument);
        }
/// <summary>
/// Change the pdf document page orientation 
/// </summary>
/// <param name="document">pdf document to change the page orientation</param>
/// <param name="isOrientationChanged">to identify the page orientation was changed</param>
private PdfDocument ChangeOrientation(PdfDocument document, bool isOrientationChanged)
        {
            document.PageSettings.Margins.All = 0;
            foreach (PdfPageBase loadedPage in loadedDocument.Pages)
            {
                float width = loadedPage.Size.Width;
                float height = loadedPage.Size.Height;
                if (loadedPage.Rotation == PdfPageRotateAngle.RotateAngle90 ||
                    loadedPage.Rotation == PdfPageRotateAngle.RotateAngle270)
                {
                    width = loadedPage.Size.Height;
                    height = loadedPage.Size.Width;
                }
 
                //Change the orientation
                if (width > height)
                    document.PageSettings.Orientation = PdfPageOrientation.Portrait;
                else
                    document.PageSettings.Orientation = PdfPageOrientation.Landscape;
                document.PageSettings.Size = new SizeF(width, height);
 
                //Add pages to new document
                PdfPage page = document.Pages.Add();
                PdfGraphics graphics = page.Graphics;
                PdfTemplate template = loadedPage.CreateTemplate();
 
                //Convert landscape to portrait
                if (document.PageSettings.Orientation == PdfPageOrientation.Landscape)
                {
                    PdfGraphicsState state = graphics.Save();
                    graphics.TranslateTransform(height / 2, width / 2);
                    if (!isOrientationChanged)
                    {
                        graphics.ScaleTransform(width / height, width / height);
                    }
                    else
                    {
                        graphics.ScaleTransform(height / width, height / width);
                    }
                    if (loadedPage.Rotation == PdfPageRotateAngle.RotateAngle90)
                    {
                        graphics.RotateTransform(90);
                        graphics.TranslateTransform(-height / 2, -width / 2);
                    }
                    else if (loadedPage.Rotation == PdfPageRotateAngle.RotateAngle270)
                    {
                        graphics.RotateTransform(270);
                        graphics.TranslateTransform(-height / 2, -width / 2);
                    }
                    else if (loadedPage.Rotation == PdfPageRotateAngle.RotateAngle180)
                    {
                        graphics.RotateTransform(180);
                        graphics.TranslateTransform(-width / 2, -height / 2);
                    }
                    else
                    {
                        graphics.TranslateTransform(-width / 2, -height / 2);
                    }
                    graphics.DrawPdfTemplate(template, new PointF(0, 0));
                    graphics.Restore(state);
                }
                //Convert portrait to landscape
                else
                {
                    PdfGraphicsState state = graphics.Save();
                    graphics.TranslateTransform(height / 2, width / 2);
                    if (!isOrientationChanged)
                    {
                        graphics.ScaleTransform(height / width, height / width);
                    }
                    else
                    {
                        graphics.ScaleTransform(width / height, width / height);
                    }
                    if (loadedPage.Rotation == PdfPageRotateAngle.RotateAngle90)
                    {
                        graphics.RotateTransform(90);
                        graphics.TranslateTransform(-height / 2, -width / 2);
                    }
                    else if (loadedPage.Rotation == PdfPageRotateAngle.RotateAngle270)
                    {
                        graphics.RotateTransform(270);
                        graphics.TranslateTransform(-height / 2, -width / 2);
                    }
                    else if (loadedPage.Rotation == PdfPageRotateAngle.RotateAngle180)
                    {
                        graphics.RotateTransform(180);
                        graphics.TranslateTransform(-width / 2, -height / 2);
                    }
                    else
                    {
                        graphics.TranslateTransform(-width / 2, -height / 2);
                    }
                    graphics.DrawPdfTemplate(template, new PointF(0, 0));
                    graphics.Restore(state);
                }
            }
            return document;
        }