Resolvi com esse código:
MySqlConnection m_conexao = new MySqlConnection();
m_conexao.ConnectionString = ConfigurationManager.ConnectionStrings["conexaoMysql"].ConnectionString;
this.comando = new MySqlCommand(comandoSQL.ToString(), m_conexao);
try
{
m_conexao.Open();
comando.ExecuteNonQuery();
MySqlDataReader dr = comando.ExecuteReader();
if (dr.HasRows)
{
while (dr.Read())
{
cbo.Items.Add(dr["CODCLI"].ToString() + "-" + dr["NOME"].ToString());
}
}
}
catch (Exception excecao)
{
Erro = excecao.Message;
}
finally
{
m_conexao.Close();
}