using System;

 using System.Collections.Generic;

 using System.Linq;

 using System.Web;

 using System.Web.UI;

 using System.Web.UI.WebControls;

 using System.Data;

 using System.Collections;

 using System.Configuration;

 using System.Data.SqlClient;

 namespace TreeView

 {

     public partial class TreeView : System.Web.UI.Page

     {

         string connection = ConfigurationManager.ConnectionStrings["SQLconnection"].ToString();

         protected void Page_Load(object sender, EventArgs e)

         {

             select();

             CreateTree();

         }

         DataSet ds = new DataSet();

         public DataSet DataS(string sql, string tablename)

         {

             SqlConnection con = new SqlConnection(connection);

             SqlDataAdapter sqlda = new SqlDataAdapter(sql, con);

             sqlda.Fill(ds, tablename);

             return ds;

         }

         //ParentMenu:父节点,

         //Grade:标识这是第几级节点,

         //Flag:标识是不是尾结点，1是 0 不是,

         //href:指向的链接

         public void select()

         {

             string sql = "select * from treeview";

             ds = DataS(sql, "test");

         }

         public void CreateTree()

         {

             try

             {

                 DataTable dt = ds.Tables["test"];

                 SortedList sl = new SortedList();

                 TreeNode tn = new TreeNode();

                 if (dt.Rows.Count <= )

                 {

                     tn.Text = "空";

                     tn.Value = "";

                     tn.NavigateUrl = "";

                     tn.Target = "";

                     tn.Expanded = false;

                     tn.SelectAction = TreeNodeSelectAction.SelectExpand;

                 }

                 else

                 {

                     for (int i = ; i < dt.Rows.Count; i++)

                     {

                         //创建父节点

                         if (dt.Rows[i]["Grade"].ToString() == "")

                         {

                             TreeNode node = new TreeNode();

                             node.Text = dt.Rows[i]["MenuName"].ToString();

                             node.Value = dt.Rows[i]["MenuID"].ToString();

                             if (dt.Rows[i]["Flag"].ToString() == "")

                             {

                                 node.NavigateUrl = dt.Rows[i]["href"].ToString();

                                 tn.Target = "_bank";

                             }

                             node.Expanded = false;

                             node.SelectAction = TreeNodeSelectAction.Expand;

                             sl.Add(node.Value, node);

                             tv_Method.Nodes.Add(node);

                         }

                         else

                         {

                             //查找父节点

                             TreeNode ParentNod = (TreeNode)sl.GetByIndex(sl.IndexOfKey(dt.Rows[i]["ParentMenu"].ToString()));

                             //创建子节点

                             TreeNode tnChild = new TreeNode();

                             tnChild.Text = dt.Rows[i]["MenuName"].ToString();

                             tnChild.Value = dt.Rows[i]["MenuID"].ToString();

                             if (dt.Rows[i]["Flag"].ToString() == "")

                             {

                                 tnChild.NavigateUrl = dt.Rows[i]["href"].ToString();

                                 tnChild.Target = "_bank";

                             }

                             tnChild.Expanded = false;

                             tnChild.SelectAction = TreeNodeSelectAction.Expand;

                             sl.Add(tnChild.Value, tnChild);

                             ParentNod.ChildNodes.Add(tnChild);

                         }

                     }

                 }

             }

             catch (Exception ex)

             {

                 throw ex;

             }

         }

     }

 }