Repeater 主从嵌套的有关问题

  protected void Page_Load(object sender, EventArgs e)
        {
            if (!Page.IsPostBack)
                BindItems();
        }

        protected void BindItems() //绑定分类
        {
            BGOA.App_Code.ItemsDal itemsDal = new App_Code.ItemsDal();
            ItemsRepeater.DataSource = itemsDal.GetItemsListForIndex();
            ItemsRepeater.DataBind();
        }

        protected DataTable BindNews(int itemsid) //根据分类ID,绑定新闻列表
        {
            BGOA.App_Code.NewsDal newsdal = new App_Code.NewsDal();
            return  newsdal.GetNewsForIndex(itemsid);
        }

<asp:Repeater ID="ItemsRepeater" runat="server">
                    <ItemTemplate>
                        <div class="column">
                            <h3><%# Eval("ItemName") %><a href="#">更多</a></h3>
                            <ul>
                                <asp:Repeater ID="NewsRepeater" runat="server"  DataSourceID='<%#BindNews(Convert.ToInt32(Eval("ItemID"))) %>'>
                                    <ItemTemplate>
                                        <li><%#Eval("NewsTitle") %></li>
                                    </ItemTemplate>
                                </asp:Repeater>
                            </ul>