在asp.net里怎么根据用户权限来生成树形菜单

在asp.net里怎么跟据用户权限来生成树形菜单
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using Microsoft.Web.UI.WebControls;
using System.Data.SqlClient;
namespace TreeCS
{
/// <summary>
/// WebForm1 的摘要说明。
/// </summary>
public class WebForm1 : System.Web.UI.Page
{
   protected Microsoft.Web.UI.WebControls.TreeView TreeView1;
   private void Page_Load(object sender, System.EventArgs e)
   {
    // 定义数据库连接
    SqlConnection CN = new SqlConnection();
    try
    {
     //初始化连接字符串
     CN.ConnectionString= "data source=pmserver;initial catalog=Benchmark;persist security info=False;user id=sa;Password=sa;";
     CN.Open();
     SqlDataAdapter adp = new SqlDataAdapter("select * from tbTree",CN);
     DataSet ds=new DataSet();
     adp.Fill(ds);
     this.ViewState["ds"]=ds;
    }
    catch (Exception ex)
    {
     Session["Error"] = ex.ToString();
     Response.Redirect("error.aspx");        //跳转程序的公共错误处理页面
    }
    finally
    {
     CN.Close();
    }
    //调用递归函数，完成树形结构的生成
    AddTree(0, (TreeNode)null);
   }
   // 递归添加树的节点
   public void AddTree(int ParentID,TreeNode pNode)
   {
    DataSet ds=(DataSet) this.ViewState["ds"];
  &nb