public Billet(int _id, int _client, int _vol, DateTime _date)
        {
            this.id     = _id;
            this.client = _client;

            Tarif.Tarif t = DAL_Tarif.GetTarif(DAL_TarifVol.GetTarifVol(_vol).Tarif);
            this.classe = DAL_Classe.GetClasse(t.Classe).Nom;
            this.tarif  = t.Nom;
            this.prix   = DAL_TarifVol.GetTarifVol(_vol).Prix;

            Vol.Vol vol = DAL_Vol.GetVol(DAL_TarifVol.GetTarifVol(_vol).Vol);
            this.trajet  = vol.StrTrajet;
            this.depart  = vol.Depart;
            this.arrivee = vol.Arrivee;

            this.date = _date;
        }
        public static List <string> SelectNomTarifsWithClasse()
        {
            List <string> Tarifs = new List <string>();

            bdd.OpenConnection();
            string       query = "SELECT * FROM tarif;";
            MySqlCommand cmd   = new MySqlCommand(query, bdd.GetConnection());

            cmd.ExecuteNonQuery();
            MySqlDataReader reader = cmd.ExecuteReader();

            while (reader.Read())
            {
                Tarif Tarif = new Tarif(reader.GetInt32(0), reader.GetInt32(1), reader.GetString(2));
                Tarifs.Add(DAL_Classe.GetClasse(Tarif.Classe) + " - " + Tarif.Nom);
            }
            reader.Close();
            bdd.CloseConnection();
            return(Tarifs);
        }