public void AddClient(string clientName, string clientSurname, string clientCode, string phoneNo, string email, out bool status) { status = true; DAClient dAClient = new DAClient(); DataTable data = dAClient.GetClientList(-1, "", "", "", "", ""); for (int i = 0; i < data.Rows.Count; i++) { if (clientCode == data.Rows[i]["ClientCode"].ToString()) { status = false; return; } } if (status) { dAClient.Add(clientName, clientSurname, clientCode, phoneNo, email); } return; }