Remplir un combobox à partir d'une BDD

public class cMySql
    {
        private MySqlConnection pMySQL;
        private string sHost = "";
        private int iPort = 0;
        private string sUser = "";
        private string sPassword = "";
        private string sDatabase = "";
        private string sConnexionstring = "";
        private string Erreur = "";
        private bool bIsOk = false;
        private int iResultInFic;
        private string[] lastResult;
        //--constructeurs. Se connecte au moment de l'initialisation
        public cMySql()
            : this("127.0.0.1", 22, "root", "", "")
        {
        }
        public cMySql(string tsHost, int tiPort, string tsUser, string tsPassword, string tsDatabase)
        {
            sHost = tsHost;
            iPort = tiPort;
            sUser = tsUser;
            sPassword = tsPassword;
            sDatabase = tsDatabase;
            sConnexionstring = "server=" + sHost + ";User Id=" + sUser + ";password=" + sPassword + ";database=" + sDatabase + ";Allow User Variables=true";
            connect();
        }
        private void connect()
        {
            pMySQL = new MySqlConnection(sConnexionstring);
            pMySQL.Open();
        }
        //--recuperer la derniere erreur
        public string GetErreur() { return Erreur; }
        //--lancer une requete de type query. renvoi {0:pas de resultats,1:ok,2:erreur}
        public int Query(string sQuery)//améliorer la récupération des résultats, à 16.000.000 de resultats, on se fait jeter
        {
            foreach(string s in Directory.GetFiles(@"c:\*.dump"))
                File.Delete(s);
            iResultInFic = 0;
            Erreur = "";
            lastResult = new string[0];
            bIsOk = false;
            int retour = 0;
            MySqlCommand cmdMySQL = pMySQL.CreateCommand();
            cmdMySQL.CommandText = sQuery;
            MySqlDataReader reader;
            try
            {
                reader = cmdMySQL.ExecuteReader();
            }
            catch (MySqlException e)
            {
                Erreur = e.Message.ToString();
                return 2;
            }
            bIsOk = true;
            int nbChamps = reader.FieldCount - 1;
            string res = "";
            List<String> tab = new List<String>();
            while (reader.Read())
            {
                for (int i = 0; i <= nbChamps; i++)
                    res += reader.GetValue(i) + ";";

                try
                {
                    tab.Add(res);
                }
                catch (OutOfMemoryException e)
                {
                    iResultInFic ++;
                    using (StreamWriter sw = new StreamWriter(@"c:\tmpSql_" + iResultInFic.ToString() + ".dump"))
                        foreach (string s in tab)
                            sw.WriteLine(s);
                    tab.Clear();
                    tab.Add(res);
                }
                res = "";
            }
            if (tab.Count > 0)
                retour = 1;
            lastResult = new string[tab.Count];
            int j = 0;
            foreach (string s in tab)
            {
                lastResult[j] = s;
                j++;
            }
            reader.Close();
            return retour;
        }

        //--Executer une requete select, renvoi les résultats dans un tableau de string, chaque colonnes séparées par un ';', renvoi l'exeption en cas d'erreur 
        public string[] getRes()
        {
            if (!bIsOk)
            {
                if (Erreur != "")
                {
                    Exception e = new Exception(Erreur);
                    throw e;
                }
                else
                {
                    Exception e = new Exception("PAS DE REQUETE");
                    throw e;
                }
            }
            if (iResultInFic > 0)
            {
                throw new Exception("ficRes");
            }
            return lastResult;
        }

        //--Executer une requete insert, 0 en cas d'erreur, 1 si ok
        public int Exec(string sExec)
        {
            MySqlCommand cmdMySQL = pMySQL.CreateCommand();
            Erreur = "";
            cmdMySQL.CommandText = sExec;
            try
            {
                cmdMySQL.ExecuteNonQuery();
            }
            catch (MySqlException e)
            { Erreur = e.Message.ToString(); return 0; }

            return 1;
        }

        //--récupérer edernier identifiant insérer
        public int lastInsertId()
        {
            MySqlCommand cmdMySQL = pMySQL.CreateCommand();
            cmdMySQL.CommandText = "SELECT LAST_INSERT_ID()";
            MySqlDataReader reader = cmdMySQL.ExecuteReader();
            try
            {
                if (reader.Read())
                {
                    return reader.GetInt32(0);
                }
                else
                {
                    return 0;
                }
            }
            finally
            {
                reader.Close();
            }
        }

        //--modifier base
        public void set_base(String tsBase)
        {
            sDatabase = tsBase;
            sConnexionstring = "server=" + sHost + ";User Id=" + sUser + ";password=" + sPassword + ";database=" + sDatabase + ";Allow User Variables=true";
            connect();
        }
    }

taCombo.Items.Add(uneValeurEnString)