Sample Code VB.NET
Imports SelectPdf Namespace Controllers Public Class PdfFormFillingController Inherits Controller ' GET: PdfFormFilling Public Function Index() As ActionResult Return View() End Function <HttpPost> _ Public Function SubmitAction(collection As FormCollection) As ActionResult ' the initial file Dim file As String = Server.MapPath("~/files/w-9.pdf") ' load the pdf form manager Dim form As New PdfFormManager() form.Load(file) ' fill some fields Dim name As PdfFormFieldTextBox = TryCast(form.Fields("f1_1"), PdfFormFieldTextBox) name.Text = "This is my name" Dim businessName As PdfFormFieldTextBox = TryCast(form.Fields("f1_2"), PdfFormFieldTextBox) businessName.Text = "This is my business name" Dim clasifIndividual As PdfFormFieldCheckBox = TryCast(form.Fields("c1_1"), PdfFormFieldCheckBox) clasifIndividual.Checked = True Dim address As PdfFormFieldTextBox = TryCast(form.Fields("f1_7"), PdfFormFieldTextBox) address.Text = "This is my address" Dim city As PdfFormFieldTextBox = TryCast(form.Fields("f1_8"), PdfFormFieldTextBox) city.Text = "This is my city" Dim employer1 As PdfFormFieldTextBox = TryCast(form.Fields("f1_14"), PdfFormFieldTextBox) employer1.Text = "XX" Dim employer2 As PdfFormFieldTextBox = TryCast(form.Fields("f1_15"), PdfFormFieldTextBox) employer2.Text = "1234567" Dim ssn1 As PdfFormFieldTextBox = TryCast(form.Fields("f1_11"), PdfFormFieldTextBox) ssn1.Text = "123" Dim ssn2 As PdfFormFieldTextBox = TryCast(form.Fields("f1_12"), PdfFormFieldTextBox) ssn2.Text = "45" Dim ssn3 As PdfFormFieldTextBox = TryCast(form.Fields("f1_13"), PdfFormFieldTextBox) ssn3.Text = "6789" ' save pdf document Dim pdf As Byte() = form.Save() ' close pdf document form.Close() ' return resulted pdf document Dim fileResult As FileResult = New FileContentResult(pdf, "application/pdf") fileResult.FileDownloadName = "Document.pdf" Return fileResult End Function End Class End Namespace