protected void btnAnnuleer_Click(object sender, EventArgs e) { Button btn = (Button)sender; int TicketID = Int32.Parse(btn.ToolTip.ToString()); TicketAccess t = new TicketAccess(); DataTable table = t.getDatum(TicketID); string date = table.Rows[0][0].ToString(); DateTime d = DateTime.Parse(date); DateTime today = new DateTime(); if (d.AddDays(3) >= today) { t.AnnuleerTicket(TicketID); updateRitten(); } else { Response.Write("<script LANGUAGE='JavaScript'>alert('Deze Rit kan niet worden geannuleerd!');</script>"); } }