เอา Code ASP.Net มาฝาก export pdf ไทย + page number ด้วย iTextSharp

using System.IO;
using iTextSharp.text;
using iTextSharp.text.html.simpleparser;
using iTextSharp.text.pdf;
using System.Data;
using System.Text;
using System.Web.UI.HtmlControls;

public partial class pm_Default2 : System.Web.UI.Page
{

   protected void btnExportPdf_Click(object sender, EventArgs e)
    {
        //set font ในกรณีที่เป็นภาษาไทนแนะนำให้ใช้ เป็น font Sarabun ของ sipa
        BaseFont bf = BaseFont.CreateFont(Server.MapPath("~/Fonts/THSarabunNew.ttf"), BaseFont.IDENTITY_H, BaseFont.EMBEDDED);

        Font defaultFont = new Font(bf, 12);
        Font header = new Font(bf, 14, Font.BOLD);
        Font headTB = new Font(bf, 12, Font.BOLD);

        Response.ContentType = "application/pdf";
        Response.AddHeader("Content-Disposition", "attachment;filename=Report.pdf");
        Response.Cache.SetCacheability(HttpCacheability.NoCache);
        StringWriter sw = new StringWriter();
        HtmlTextWriter hw = new HtmlTextWriter(sw);
        //this.Page.RenderControl(hw); แปลงข้อมูลทั้งหน้าให้เป็น pdf

        StringReader sr = new StringReader(sw.ToString());
        Document pdfDoc = new Document(PageSize.A4, 25f, 25f, 25f, 15f); // left , right , top , bottom

        HTMLWorker htmlparser = new HTMLWorker(pdfDoc);
        //PdfWriter.GetInstance(pdfDoc, Response.OutputStream);

        PdfWriter writer = PdfWriter.GetInstance(pdfDoc, Response.OutputStream);
        // calling PDFFooter class to Include in document
        writer.PageEvent = new PDFFooter();


        // เอาข้อมูลใน GridView1 มาใส่ใน PdfTable
        PdfPTable PdfTable = new PdfPTable(GridView1.Columns.Count);
        PdfPCell PdfPCell = null;

        // Write Header ที่ PdfCell ใน PdfTable
        for (int column = 0; column < GridView1.Columns.Count; column++)
        {
            PdfPCell = new PdfPCell(new Phrase(new Chunk(GridView1.Columns[column].HeaderText.ToString(), headTB)));
            PdfPCell.Column.Alignment = Element.ALIGN_CENTER;
            PdfTable.AddCell(PdfPCell);
        }

        // Write Data ที่ PdfCell ใน PdfTable
        for (int row = 0; row < GridView1.Rows.Count; row++)
        {
            for (int col = 0; col < GridView1.Columns.Count; col++)
            {
                PdfPCell = new PdfPCell(new Phrase(new Chunk(GridView1.Rows[row].Cells[col].Text, defaultFont)));
                PdfTable.AddCell(PdfPCell);

            }
        }


        PdfTable.TotalWidth = 530f; // ความยาวของตาราง
        PdfTable.LockedWidth = true;

        pdfDoc.Open();


        Paragraph head1 = new Paragraph(lblHeader.Text, header); //สร้างหัวข้อใหม่
        head1.Alignment = Element.ALIGN_CENTER; // เซ็ทให้อยู่ตรงกลาง
        pdfDoc.Add(head1); //เพิ่มลงใน pdf

        pdfDoc.Add(PdfTable); //เพิ่ม table ที่เอามาจาก gridview ลงใน pdf


        pdfDoc.Close();

        Response.Write(pdfDoc);
        Response.End();



    }


}



// ********  ส่วน 2 class ด้านล่างเป็นการทำ page number , header , footer (ถ้าไม่อยากแก้อะไรมาแค่ copy วาง จบ) **********//

public class PDFFooter : PdfPageEventHelper
{
   
    // หัวข้อเฉพาะหน้าแรก
    public override void OnOpenDocument(PdfWriter writer, Document document)
    {
        base.OnOpenDocument(writer, document);

        /*
        PdfPTable tabFot = new PdfPTable(new float[] { 1F });
        
        tabFot.SpacingAfter = 10F;
        PdfPCell cell;
        tabFot.TotalWidth = 300F;

        int pageN = writer.PageNumber;
        String text = "Page " + pageN + " of ";
        
        cell = new PdfPCell(new Phrase(text));
        cell.Border = 0;
        cell.HorizontalAlignment = Element.ALIGN_RIGHT;

        tabFot.DefaultCell.Border = 0;
        tabFot.AddCell(cell);
        tabFot.WriteSelectedRows(0, -1, 150, document.Top, writer.DirectContent);
         */
    }

    // write on start of each page
    public override void OnStartPage(PdfWriter writer, Document document)
    {
        base.OnStartPage(writer, document);
    }

    // write on end of each page
    public override void OnEndPage(PdfWriter writer, Document document)
    {
        /*---- set font ----*/
        BaseFont bf = BaseFont.CreateFont(
                         BaseFont.TIMES_ROMAN,
                         BaseFont.CP1252,
                         BaseFont.EMBEDDED);
        Font font = new Font(bf, 12);

        /*---- set page number ----*/
        base.OnEndPage(writer, document);
        PdfPTable tabFot = new PdfPTable(new float[] { 1F });
        tabFot.TotalWidth = 300F;
        int pageN = writer.PageNumber;        
        String text = "Page : " + pageN  ;
        PdfPCell cell = new PdfPCell(new Phrase(text, font));
        cell.Border = 0;
        cell.HorizontalAlignment = Element.ALIGN_RIGHT;
        Rectangle pageSize = document.PageSize;
        tabFot.DefaultCell.Border = 0;
        tabFot.AddCell(cell);
        document.SetMargins(25f, 25f, 35f, 15f);
        tabFot.WriteSelectedRows(0, -1, pageSize.GetLeft(280), pageSize.GetTop(10), writer.DirectContent);


        /*---- set footer----*/


    }

    //write on close of document
    public override void OnCloseDocument(PdfWriter writer, Document document)
    {
        base.OnCloseDocument(writer, document);
    }
}


public class PageEventHelper : PdfPageEventHelper
    {
     public class TwoColumnHeaderFooter : PdfPageEventHelper
     {
         // This is the contentbyte object of the writer
         PdfContentByte cb;

         // we will put the final number of pages in a template
         PdfTemplate template;

         // this is the BaseFont we are going to use for the header / footer
         BaseFont bf = null;

         // This keeps track of the creation time
         DateTime PrintTime = DateTime.Now;

         #region Properties
         private string _Title;
         public string Title
         {
             get { return _Title; }
             set { _Title = value; }
         }

         private string _HeaderLeft;
         public string HeaderLeft
         {
             get { return _HeaderLeft; }
             set { _HeaderLeft = value; }
         }

         private string _HeaderRight;
         public string HeaderRight
         {
             get { return _HeaderRight; }
             set { _HeaderRight = value; }
         }

         private Font _HeaderFont;
         public Font HeaderFont
         {
             get { return _HeaderFont; }
             set { _HeaderFont = value; }
         }

         private Font _FooterFont;
         public Font FooterFont
         {
             get { return _FooterFont; }
             set { _FooterFont = value; }
         }
         #endregion

         // we override the onOpenDocument method
         public override void OnOpenDocument(PdfWriter writer, Document document)
         {
             try
             {
                 PrintTime = DateTime.Now;
                 bf = BaseFont.CreateFont(BaseFont.HELVETICA, BaseFont.CP1252, BaseFont.NOT_EMBEDDED);
                 cb = writer.DirectContent;
                 template = cb.CreateTemplate(50, 50);
             }
             catch (DocumentException de)
             {
             }
             catch (System.IO.IOException ioe)
             {
             }
         }

         public override void OnStartPage(PdfWriter writer, Document document)
         {
             base.OnStartPage(writer, document);

             Rectangle pageSize = document.PageSize;

             if (Title != string.Empty)
             {
                 cb.BeginText();
                 cb.SetFontAndSize(bf, 15);
                 cb.SetRGBColorFill(50, 50, 200);
                 cb.SetTextMatrix(pageSize.GetLeft(40), pageSize.GetTop(40));
                 cb.ShowText(Title);
                 cb.EndText();
             }

             if (HeaderLeft + HeaderRight != string.Empty)
             {
                 PdfPTable HeaderTable = new PdfPTable(2);
                 HeaderTable.DefaultCell.VerticalAlignment = Element.ALIGN_MIDDLE;
                 HeaderTable.TotalWidth = pageSize.Width - 80;
                 HeaderTable.SetWidthPercentage(new float[] { 45, 45 }, pageSize);

                 PdfPCell HeaderLeftCell = new PdfPCell(new Phrase(8, HeaderLeft, HeaderFont));
                 HeaderLeftCell.Padding = 5;
                 HeaderLeftCell.PaddingBottom = 8;
                 HeaderLeftCell.BorderWidthRight = 0;
                 HeaderTable.AddCell(HeaderLeftCell);

                 PdfPCell HeaderRightCell = new PdfPCell(new Phrase(8, HeaderRight, HeaderFont));
                 HeaderRightCell.HorizontalAlignment = PdfPCell.ALIGN_RIGHT;
                 HeaderRightCell.Padding = 5;
                 HeaderRightCell.PaddingBottom = 8;
                 HeaderRightCell.BorderWidthLeft = 0;
                 HeaderTable.AddCell(HeaderRightCell);

                 cb.SetRGBColorFill(0, 0, 0);
                 HeaderTable.WriteSelectedRows(0, -1, pageSize.GetLeft(40), pageSize.GetTop(50), cb);
             }
         }

         public override void OnEndPage(PdfWriter writer, Document document)
         {
             base.OnEndPage(writer, document);

             int pageN = writer.PageNumber;
             String text = "Page " + pageN + " of ";
             float len = bf.GetWidthPoint(text, 8);

             Rectangle pageSize = document.PageSize;

             cb.SetRGBColorFill(100, 100, 100);

             cb.BeginText();
             cb.SetFontAndSize(bf, 8);
             cb.SetTextMatrix(pageSize.GetLeft(40), pageSize.GetBottom(30));
             cb.ShowText(text);
             cb.EndText();

             cb.AddTemplate(template, pageSize.GetLeft(40) + len, pageSize.GetBottom(30));

             cb.BeginText();
             cb.SetFontAndSize(bf, 8);
             cb.ShowTextAligned(PdfContentByte.ALIGN_RIGHT,
                 "Printed On " + PrintTime.ToString(),
                 pageSize.GetRight(40),
                 pageSize.GetBottom(30), 0);
             cb.EndText();
         }

         public override void OnCloseDocument(PdfWriter writer, Document document)
         {
             base.OnCloseDocument(writer, document);

             template.BeginText();
             template.SetFontAndSize(bf, 8);
             template.SetTextMatrix(0, 0);
             template.ShowText("" + (writer.PageNumber - 1));
             template.EndText();
         }

     }
    }