How does one implement a footer and a header on pdf. i get the  error yet i av used references required. as shown below.

@using iTextSharp.text;
@using iTextSharp.text.pdf;
@using iTextSharp.text.html;

...

HeaderFooter footer = new HeaderFooter(new Phrase("Page: "), true);
doc.Footer = footer;
HeaderFooter header = new HeaderFooter(new Phrase("Image scanned on " + DateAndTime.Now.ToString("dd/MM/yyyy")), false);
doc.Header = header;
for (int i = 1; i <= 2; i++) {
doc.NewPage();
.....