How to fill continuous page number in pdf form field

//Load the template document
PdfLoadedDocument doc = new PdfLoadedDocument(”Form.pdf");
PdfLoadedForm form = doc.Form;
// fill the fields from the first page
(form.Fields["f1-1"] as PdfLoadedTextBoxField).Text = "1";
(form.Fields["f1-2"] as PdfLoadedTextBoxField).Text = "1";
(form.Fields["f1-3"] as PdfLoadedTextBoxField).Text = "1";
(form.Fields["f1-4"] as PdfLoadedTextBoxField).Text = "3";
(form.Fields["f1-5"] as PdfLoadedTextBoxField).Text = "1";
(form.Fields["f1-6"] as PdfLoadedTextBoxField).Text = "1";
(form.Fields["f1-7"] as PdfLoadedTextBoxField).Text = "22";
(form.Fields["f1-8"] as PdfLoadedTextBoxField).Text = "30";
(form.Fields["f1-9"] as PdfLoadedTextBoxField).Text = "John";
(form.Fields["f1-10"] as PdfLoadedTextBoxField).Text = "Doe";
(form.Fields["f1-11"] as PdfLoadedTextBoxField).Text = "3233 Spring Rd.";
(form.Fields["f1-12"] as PdfLoadedTextBoxField).Text = "Atlanta, GA 30339";
(form.Fields["c1-1[0]"] as PdfLoadedCheckBoxField).Items[0].Checked = true;
(form.Fields["c1-1[1]"] as PdfLoadedCheckBoxField).Items[0].Checked = true;
// fill the fields from the second page
(form.Fields["f2-1"] as PdfLoadedTextBoxField).Text = "3200";
(form.Fields["f2-2"] as PdfLoadedTextBoxField).Text = "4850";
(form.Fields["f2-3"] as PdfLoadedTextBoxField).Text = "0";
(form.Fields["f2-4"] as PdfLoadedTextBoxField).Text = "500";
(form.Fields["f2-5"] as PdfLoadedTextBoxField).Text = "500";
(form.Fields["f2-6"] as PdfLoadedTextBoxField).Text = "800";
(form.Fields["f2-7"] as PdfLoadedTextBoxField).Text = "0";
(form.Fields["f2-8"] as PdfLoadedTextBoxField).Text = "0";
(form.Fields["f2-9"] as PdfLoadedTextBoxField).Text = "3";
(form.Fields["f2-10"] as PdfLoadedTextBoxField).Text = "3";
(form.Fields["f2-11"] as PdfLoadedTextBoxField).Text = "3";
(form.Fields["f2-12"] as PdfLoadedTextBoxField).Text = "2";
doc.Save("sample.pdf");