A PDF page is represented by the PdfPage class. A PDF document has a collection of pages given by the PdfDocumentPages property. A new page can be added to the PDF document using one of the PdfDocumentAddPage overloaded methods or the PdfDocumentAddPageAtIndex method.
// URL 2 is laid out on a new page with the selected orientation
PdfPage page2 = document.AddPage(PdfPageSize.A4, new PdfMargins(5), GetSelectedPageOrientation());
// layout the HTML from URL 2
PdfHtml html2 = new PdfHtml(textBoxUrl2.Text);
html2.WaitBeforeConvert = 2;
page2.Layout(html2);
// add an orange border to each PDF page in the loaded PDF document
foreach (PdfPage pdfPage in document.Pages)
{
float crtPdfPageWidth = pdfPage.Size.Width;
float crtPdfPageHeight = pdfPage.Size.Height;
// create a PdfRectangle object
PdfRectangle pdfRectangle = new PdfRectangle(2, 2, crtPdfPageWidth - 4, crtPdfPageHeight - 4);
pdfRectangle.LineStyle.LineWidth = 2;
pdfRectangle.ForeColor = PdfColor.OrangeRed;
// layout the rectangle in PDF page
pdfPage.Layout(pdfRectangle);
}