How to export datagridview data in pdf

How to export datagridview data in pdf i was googling but i can't found yet so please guys if you know about it please give me the solution with your code please don't put any link of any articles.

What I have tried:

public void ExportToPdf(DataTable dt)
               {
                   Document document = new Document();
                   PdfWriter writer = PdfWriter.GetInstance(document, new FileStream("c://sample.pdf", FileMode.Create));
                   document.Open();
                   iTextSharp.text.Font font5 = iTextSharp.text.FontFactory.GetFont(FontFactory.HELVETICA, 5);

                   PdfPTable table = new PdfPTable(dt.Columns.Count);
                   PdfPRow row = null;
                   float[] widths = new float[] { 4f, 4f, 4f, 4f };

                   table.SetWidths(widths);

                   table.WidthPercentage = 100;
                   int iCol = 0;
                   string colname = "";
                   PdfPCell cell = new PdfPCell(new Phrase("Products"));

                   cell.Colspan = dt.Columns.Count;

                   foreach (DataColumn c in dt.Columns)
                   {

                       table.AddCell(new Phrase(c.ColumnName, font5));
                   }

                   foreach (DataRow r in dt.Rows)
                   {
                       if (dt.Rows.Count > 0)
                       {
                           table.AddCell(new Phrase(r[0].ToString(), font5));
                           table.AddCell(new Phrase(r[1].ToString(), font5));
                           table.AddCell(new Phrase(r[2].ToString(), font5));
                           table.AddCell(new Phrase(r[3].ToString(), font5));
                       }
                   } document.Add(table);
                   document.Close();
               }