ASP.NET 无限级树的加载

OPW_XT_MK OP_W_XT_MK = new OPW_XT_MK(AppPublic.GetConnectionString());
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            //生成树
            buildTree();
        }
    }

    /**//// <summary>
    /// 添加树形菜单的结构
    /// </summary>
    private void buildTree()
    {
        OP_W_XT_MK.GetMKMC(CurrentUser.Id, 0);
        foreach (DataRow dbRow in OP_W_XT_MK.dataView.Table.Rows)
        {
            if (int.Parse(dbRow[TABLE_W_XT_MK.COLUMN_SJBH].ToString()) == 0)
            {
                TreeNode newNode;
                //添加node属性
                newNode = CreateNode(dbRow[TABLE_W_XT_MK.COLUMN_MKMC].ToString(), false);
                TV_menu.Nodes.Add(newNode);
                PopulateSubTree(dbRow, newNode);
            }
        }
    }

    /**//// <summary>
    /// 添加子节点
    /// </summary>
    /// <param name="dbRow">表的一行数据</param>
    /// <param name="node">节点</param>
    private void PopulateSubTree(DataRow dbRow, TreeNode node)
    {
        //点击该节点则指向与这个节点相关的业务处理页面
        node.NavigateUrl = dbRow[TABLE_W_XT_MK.COLUMN_URL].ToString();

        foreach (DataRow childRow in OP_W_XT_MK.dataView.Table.Select(TABLE_W_XT_MK.COLUMN_SJBH + "=" + dbRow[TABLE_W_XT_MK.COLUMN_MKBH].ToString()))
        {
            TreeNode childNode = CreateNode(childRow[TABLE_W_XT_MK.COLUMN_MKMC].ToString(), false);
            childNode.Value = childRow[TABLE_W_XT_MK.COLUMN_MKBH].ToString();
            node.ChildNodes.Add(childNode);
            PopulateSubTree(childRow, childNode);
        }
    }

    /**//// <summary>
    /// 添加node 的属性  expanded 的属性是设置节点是否展开.
    /// </summary>
    /// <param name="text">节点显示内容</param>
    /// <param name="expanded">设置节点是否展开</param>
    /// <returns>树节点</returns>
    private TreeNode CreateNode(string text, Boolean expanded)
    {
        TreeNode node = new TreeNode();
        node.Text = text;
        node.Expanded = expanded;
        return node;
    }