public static void test()
    {
        using (PdfDocument pdfDoc = new PdfDocument(new PdfWriter(@"c:temppippo.pdf")))
        {
            //Add some blank pages
            pdfDoc.AddNewPage();
            pdfDoc.AddNewPage();
            pdfDoc.AddNewPage();

            //Instantiate a Signature Form Field using factory
            PdfSignatureFormField sgnField =
                PdfFormField.CreateSignature(pdfDoc, new Rectangle(100, 100, 200, 100));

            //setting name and page
            sgnField.SetFieldName("pluto");
            sgnField.SetPage(1);

            //Adding to AcroForm
            PdfAcroForm.GetAcroForm(pdfDoc, true).AddField(sgnField);
        }
    }