问无法从另一个列表框和数据库中填充列表框

EN

        string teamSelected = listBox1.GetItemText(listBox1.SelectedItem);
        conexion = new dbconnector();

        conexion.getMembersOfTeam(ref employeesM, teamSelected);
        this.listBox2.DisplayMember = "userID";
        this.listBox2.ValueMember = "userID"; //Field in the datatable which you want to be the value of the combobox
        this.listBox2.DataSource = employeesM.Tables["users_table"];

datasetMembers.Tables.Add(employeesM);

public void getMembersOfTeam(ref DataSet datasetMembers, string teamDesired)
    {

        string query4 = "select * from users_table Where userTeam = '" + teamDesired + "'"; //added by fran to retrieve all the teams
        if (OpenConnection())
        {

            //retrieving all the teams using query3
            MySqlCommand cmd4 = new MySqlCommand(query4, connection);
            MySqlDataReader dataReader4 = cmd4.ExecuteReader();
            dataReader4.Read();

            if (dataReader4.HasRows)
            {
                //dataGridView1.Visible = true;

                DataTable employeesM = new DataTable();
                employeesM.Load(dataReader4);
                datasetMembers.Tables.Add(employeesM);

            }
            else
            {
                //dataGridView1.Visible = false;
            }


            dataReader4.Close();
            //end of retrieving teams

            CloseConnection();
        }
    }