How to export pdf both tamil & english content using C# MVC

<public void GeneratePDF()
        {
            Response.ContentType = "application/pdf";
            Response.AddHeader("content-disposition", "attachment;filename=Bloglist.pdf");
            Response.Cache.SetCacheability(HttpCacheability.NoCache);
            StringWriter sw = new StringWriter();
            HtmlTextWriter hw = new HtmlTextWriter(sw);
            var students = Session["students"];
            GridView gvdetails = new GridView();
            gvdetails.AllowPaging = false;
            gvdetails.DataSource = students;
            gvdetails.DataBind();
            gvdetails.RenderControl(hw);
            gvdetails.HeaderRow.Style.Add("width", "15%");
            gvdetails.HeaderRow.Style.Add("font-size", "10px");
            gvdetails.Style.Add("text-decoration", "none");
            iTextSharp.text.Font ft = new iTextSharp.text.Font();
            FontFactory.Register(@"C:\WINDOWS\Fonts\VANAVIL-Avvaiyar_0.ttf", "VANAVIL-Avvaiyar_0.ttf");
            ft = FontFactory.GetFont("VANAVIL-Avvaiyar_0.ttf");
            gvdetails.Style.Add("font-family", "Arial, Helvetica, sans-serif ,ft;");
            gvdetails.Style.Add("font-size", "8px");
            StringReader sr = new StringReader(sw.ToString());
            iTextSharp.text.Document pdfDoc = new iTextSharp.text.Document(iTextSharp.text.PageSize.A2, 7f, 7f, 7f, 0f);
            HTMLWorker htmlparser = new HTMLWorker(pdfDoc);
            PdfWriter.GetInstance(pdfDoc, Response.OutputStream);
            pdfDoc.Open();
            htmlparser.Parse(sr);
            pdfDoc.Close();
            Response.Write(pdfDoc);
            Response.End();
        }