Add new page with content to existing PDF using iTextSharp and C# in ASP.Net

Hi ashhadsaud,

I have created the sample that full-fill your requirement.

HTML

<asp:Button ID="btnModify" Text="Add Data To New Page" runat="server" OnClick="AddDataToNewPage" />

Code

protected void AddDataToNewPage(object sender, EventArgs e)
{
    String pathin = @"F:\test.pdf";
    String pathout = @"F:\test1.pdf";
    PdfReader reader = new PdfReader(pathin);
    PdfStamper stamper = new PdfStamper(reader, new FileStream(pathout, FileMode.Create));
    PdfPCell cell = null;
    PdfPTable table = null;
    DataTable dt = GetDataTable();
    if (dt != null)
    {
        Font font8 = FontFactory.GetFont("ARIAL", 7);
        Font fontBold = FontFactory.GetFont("ARIAL", 14);
        table = new PdfPTable(dt.Columns.Count);
        cell = new PdfPCell(new Phrase(new Chunk("CustomerId", fontBold)));
        table.AddCell(cell);
        cell = new PdfPCell(new Phrase(new Chunk("CompanyName", fontBold)));
        table.AddCell(cell);
        cell = new PdfPCell(new Phrase(new Chunk("Country", fontBold)));
        table.AddCell(cell);
        for (int rows = 0; rows < dt.Rows.Count; rows++)
        {
            for (int column = 0; column < dt.Columns.Count; column++)
            {
                cell = new PdfPCell(new Phrase(new Chunk(dt.Rows[rows][column].ToString(), font8)));
                table.AddCell(cell);
            }
        }
    }
    ColumnText ct = new ColumnText(stamper.GetOverContent(1));
    ct.AddElement(table);
    Rectangle rect = new Rectangle(46, 190, 530, 36);
    ct.SetSimpleColumn(36, 36, PageSize.A4.Width - 36, PageSize.A4.Height - 175);
    ct.Go();
    Rectangle rectangle = reader.GetPageSize(1);
    int HfPgNumber = 1;
    for (int i = 1; i <= Convert.ToInt16(HfPgNumber); i++)
    {
        stamper.InsertPage(Convert.ToInt16(HfPgNumber + 1), rectangle);
        BaseFont font = BaseFont.CreateFont(BaseFont.HELVETICA_BOLD, BaseFont.CP1252, BaseFont.NOT_EMBEDDED);
        PdfContentByte overContent = stamper.GetOverContent(i + 1);
        overContent.SaveState();
        overContent.BeginText();
        overContent.SetFontAndSize(font, 10.0f);
        overContent.SetTextMatrix(100, 750);
        overContent.ShowText("This is new text added in page " + (i + 1));
        overContent.EndText();
        overContent.RestoreState();
    }
    stamper.Close();
    reader.Close();
}

private static PdfPCell PhraseCell(Phrase phrase, int align)
{
    PdfPCell cell = new PdfPCell(phrase);
    cell.BorderColor = Color.WHITE;
    cell.VerticalAlignment = PdfCell.ALIGN_TOP;
    cell.HorizontalAlignment = align;
    cell.PaddingBottom = 2f;
    cell.PaddingTop = 0f;
    return cell;
}

private DataTable GetDataTable()
{
    string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand("SELECT TOP 10 CustomerId, CompanyName, Country FROM Customers"))
        {
            using (SqlDataAdapter sda = new SqlDataAdapter())
            {
                cmd.Connection = con;
                con.Open();
                sda.SelectCommand = cmd;
                DataTable dt = new DataTable();
                sda.Fill(dt);
                return dt;
            }
        }
    }
}

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