generate pdf from richtextbox

// step 1: creation of a document-object
iTextSharp.text.Document myDocument = new iTextSharp.text.Document(PageSize.A4.Rotate());
try
{
    // step 2:
    // Now create a writer that listens to this doucment and writes the document to desired Stream.

    PdfWriter.GetInstance(myDocument, new FileStream(sfd.FileName, FileMode.Create));

    // step 3:  Open the document now using
    myDocument.Open();

    // step 4: Now add some contents to the document
    myDocument.Add(new iTextSharp.text.Paragraph(richTextBox1.Text));
}
catch (DocumentException de)
{
    Console.Error.WriteLine(de.Message);
}
catch (IOException ioe)
{
    Console.Error.WriteLine(ioe.Message);
}
// step 5: Remember to close the documnet
myDocument.Close();