private void button4_Click(object sender, EventArgs e)
        {
            //Creating iTextSharp Table from the DataTable data
            PdfPTable pdfTable = new PdfPTable(datagridview1.ColumnCount);
            pdfTable.DefaultCell.Padding = 3;
            pdfTable.WidthPercentage = 30;
            pdfTable.HorizontalAlignment = Element.ALIGN_LEFT;
            pdfTable.DefaultCell.BorderWidth = 1;

            //Adding Header row
            foreach (DataGridViewColumn column in datagridview1.Columns)
            {
                PdfPCell cell = new PdfPCell(new Phrase(column.HeaderText));
                cell.BackgroundColor = new iTextSharp.text.Color(240, 240, 240);
                pdfTable.AddCell(cell);
            }

            if (pdfTable == null)
            {
                //Adding DataRow
                foreach (DataGridViewRow row in datagridview1.Rows)
                {
                    foreach (DataGridViewCell cell in row.Cells)
                    {
                        pdfTable.AddCell(cell.Value.ToString());
                    }
                }
            }

            //Exporting to PDF
            string folderPath = "C:\Users\maury\Desktop";
            if (!Directory.Exists(folderPath))
            {
                Directory.CreateDirectory(folderPath);
            }
            using (FileStream stream = new FileStream(folderPath + "DataGridViewExport.pdf", FileMode.Create))
            {
                Document pdfDoc = new Document(PageSize.A2, 10f, 10f, 10f, 0f);
                PdfWriter.GetInstance(pdfDoc, stream);
                pdfDoc.Open();
                pdfDoc.Add(pdfTable);
                pdfDoc.Close();
                stream.Close();
            }
        }

if (pdfTable == null)
            {
                //Adding DataRow
                foreach (DataGridViewRow row in datagridview1.Rows)
                {
                    foreach (DataGridViewCell cell in row.Cells)
                    {
                        pdfTable.AddCell(cell.Value.ToString());
                    }
                }
            }