C# DataReader 使用問題....

public DataTable getSQLDTStatus(string lsSQL)
        {
            DataTable ds = new DataTable();
            if (oSQL.State == ConnectionState.Closed)
                oSQL.Open();
            using (SqlCommand cmd = new SqlCommand(lsSQL, oSQL))
            {
                cmd.CommandType = CommandType.Text;
                using (SqlDataReader sda = cmd.ExecuteReader(CommandBehavior.CloseConnection))
                {
                    ds.Load(sda);
                    //清除所使用的資源
                    sda.Close();
                    sda.Dispose();
                    return ds;
                }
            }
        }