asp.net无限级分类 TreeView

asp.net无限级分类 TreeView
这是我曾经做项目中的代码，现在将代码贴出来，希望对大家有所帮助。
tree.aspx 页面代码
<form id="form1" runat="server">
        <asp:TreeView ID="TreeView1" runat="server" ImageSet="Arrows">
            <ParentNodeStyle Font-Bold="False" />
            <HoverNodeStyle Font-Underline="True" ForeColor="#5555DD" />
            <SelectedNodeStyle Font-Underline="True" ForeColor="#5555DD" HorizontalPadding="0px"
                VerticalPadding="0px" />
            <NodeStyle Font-Names="Tahoma" Font-Size="10pt" ForeColor="Black" HorizontalPadding="5px"
                NodeSpacing="0px" VerticalPadding="0px" />
         </asp:TreeView>
    </form> 

tree.aspx.cs 后台代码
protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            AddTree(0, (TreeNode)null);
        }
    }
    //递归添加树的节点
    public void AddTree(int ParentID, TreeNode pNode)
    {
        DataView dvTree = new DataView(SWZBGL.BLL.Tel.NumberBO.GetAllTree());
        //过滤ParentID,得到当前的所有子节点
        dvTree.RowFilter = "[PARENTID] = " + ParentID;

        foreach (DataRowView Row in dvTree)