Duvida c#

public List BuscarPorSabor(string sabor)

{

List s = new List();

try
        {
            String query = "SELECT * FROM  pizza where Sabor = @Sabor";
            MySqlConnection conB = null;
            conB.Open();
            MySql.Data.MySqlClient.MySqlCommand cmd = new MySql.Data.MySqlClient.MySqlCommand(query, conB);
            cmd.Parameters.Add(new MySql.Data.MySqlClient.MySqlParameter("@Sabor", sabor));
            cmd.Prepare();

            MySqlDataReader dr = cmd.ExecuteReader();
            while (dr.Read())
            {
                Pizza pizza = new Pizza()
                {
                    sabor = dr["Sabor"].ToString(),
                    valor = Convert.ToInt32(dr["Valor"]),



                };
                s.Add(pizza);
            }

            conB.Close();

            MessageBox.Show("Sucesso");

        }
        catch (Exception ex)
        {
            MessageBox.Show("Error");

        }
        return s;
    }