private void Page_Load(object sender, System.EventArgs e)
        {
            dgQuick.SortCommand +=
                new DataGridSortCommandEventHandler(dgQuick_SortCommand);

            if (!Page.IsPostBack)
            {
                bindData("ID");
            } 
            bindData("Subject");  // LINE A ####
        }

        private void dgQuick_SortCommand(object source,
            DataGridSortCommandEventArgs e) 
        {
            // SECTION B ####
            Response.Write("dgQuick_SortCommand");
            bindData(e.SortExpression);
        }

        private void bindData(String sortExpression) 
        {        
            Response.Write(sortExpression);
            taskManager = new TaskManager(Server.MapPath(@"data\data.xml"));
            TaskList ts = taskManager.GetTaskList();
           
            TaskComparer comparer = new TaskComparer(sortExpression);
            ts.Sort(comparer);
          
            dgQuick.DataSource = ts;
            dgQuick.DataBind();

        }