Export PDF.excel in windows application using i Text sharp

private void ExportToPDF()
        {
            Form1 obj = new Form1();
            Document document = new Document(PageSize.A4, 0, 0, 50, 50);
            System.IO.MemoryStream msReport = new System.IO.MemoryStream();

            try
            {
                // creation of the different writers
                PdfWriter writer = PdfWriter.GetInstance(document, msReport);

                // we add some meta information to the document
                document.AddAuthor("eJuly");
                document.AddSubject("Export to PDF");
                PdfReader readerBicycle = null;
                readerBicycle = new PdfReader(@"c:\Temp\PDF\fw4.pdf");
                //PdfTemplate background = writer.GetImportedPage(readerBicycle, 1);


                document.Open();

                iTextSharp.text.Table datatable = new iTextSharp.text.Table(7);

                datatable.Padding = 2;
                datatable.Spacing = 0;

                float[] headerwidths = { 6, 20, 32, 18, 8, 8, 8 };
                datatable.Widths = headerwidths;

                // the first cell spans 7 columns
                Cell cell = new Cell(new Phrase("System Users Report", FontFactory.GetFont(FontFactory.HELVETICA, 16)));
                cell.HorizontalAlignment = Element.ALIGN_CENTER;
                cell.Leading = 30;
                cell.Colspan = 7;
               /// cell.Border = Rectangle.NO_BORDER;
                cell.BackgroundColor = new iTextSharp.text.Color(System.Drawing.Color.Gray);
                datatable.AddCell(cell);

                // These cells span 2 rows
                datatable.DefaultCellBorderWidth = 1;
                datatable.DefaultHorizontalAlignment = 1;
                datatable.DefaultRowspan = 2;
                datatable.AddCell("No.");
                datatable.AddCell(new Phrase("Full Name", FontFactory.GetFont(FontFactory.HELVETICA, 14)));
                datatable.AddCell("Address");
                datatable.AddCell("Telephone No.");

                // This cell spans the remaining 3 columns in 1 row
                datatable.DefaultRowspan = 1;
                datatable.DefaultColspan = 3;
                datatable.AddCell("Just Put Anything");

                // These cells span 1 row and 1 column
                datatable.DefaultColspan = 1;
                datatable.AddCell("Col 1");
                datatable.AddCell("Col 2");
                datatable.AddCell("Col 3");

                datatable.DefaultCellBorderWidth = 1;
                datatable.DefaultRowspan = 1;

                for (int i = 1; i < 20; i++)
                {
                    datatable.DefaultHorizontalAlignment = Element.ALIGN_LEFT;
                    datatable.AddCell(i.ToString());
                    datatable.AddCell("This is my name.");
                    datatable.AddCell("I have a very, very, very, very, very, very, very, very, very, very, very, very, very, very, very, very, very, very, very, very, very, very, very, very, very, very, very long long address.");
                    datatable.AddCell("0123456789");

                    datatable.DefaultHorizontalAlignment = Element.ALIGN_CENTER;
                    datatable.AddCell("No");
                    datatable.AddCell("Yes");
                    datatable.AddCell("No");
                }

                document.Add(datatable);
                writer.Open();
                writer.ClearTextWrap();
               //writer.CurrentPageNumber = 3;
                writer.GetPdfTable(datatable);
            
                //writer.DirectContentUnder;
                //writer.DirectContent;
         
                

            }
            catch (Exception e)
            {
                Console.Error.WriteLine(e.Message);
            }

            // we close the document
            document.Close();

            //obj.Show();
         
         //   Response.Clear();
            //Response.AddHeader("content-disposition", "attachment;filename=Export.pdf");
            //Response.ContentType = "application/pdf";
            //Response.BinaryWrite(msReport.ToArray());
            //Response.End();
        }