//************************* aspx *************************// <%@ Page language="c#" Codebehind="WebForm1.aspx.cs" AutoEventWireup="false" Inherits="TreeTest.WebForm1" %> <%@ Register TagPrefix="iewc" Namespace="Microsoft.Web.UI.WebControls" Assembly="Microsoft.Web.UI.WebControls" %>
<HTML> <body MS_POSITIONING="GridLayout"> <form id="Form1" method="post" runat="server"> <FONT face="宋体"> <iewc:TreeView id="TreeView1" style="Z-INDEX: 101; LEFT: 8px; POSITION: absolute; TOP: 16px" runat="server" AutoPostBack="True"></iewc:TreeView> <asp:Label id="Label1" style="Z-INDEX: 102; LEFT: 440px; POSITION: absolute; TOP: 56px" runat="server" Width="152px" Height="64px">Label</asp:Label> <asp:Label id="Label2" style="Z-INDEX: 103; LEFT: 456px; POSITION: absolute; TOP: 144px" runat="server" Width="144px" Height="48px">Label</asp:Label> <asp:Label id="Label3" style="Z-INDEX: 104; LEFT: 696px; POSITION: absolute; TOP: 64px" runat="server">Label</asp:Label></FONT> </form> </body> </HTML>
//***************************** CS *************************// 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 System.Data.OleDb; using Microsoft.Web.UI.WebControls; namespace TreeTest { /// <summary> /// WebForm1 的摘要说明。 /// </summary> public class WebForm1 : System.Web.UI.Page { protected Microsoft.Web.UI.WebControls.TreeView TreeView1; protected System.Web.UI.WebControls.Label Label1; protected System.Web.UI.WebControls.Label Label2; protected System.Web.UI.WebControls.Label Label3; OleDbConnection Con ; string dataConStr = ""; private void Page_Load(object sender, System.EventArgs e) { dataConStr = "Provider=microsoft.jet.oledb.4.0;Data Source="+Server.MapPath("tree.mdb")+";User ID=;Password=;"; Con = new OleDbConnection(dataConStr); if(!IsPostBack) { TreeNode node = new TreeNode(); node.Text = "根"; node.NodeData = "0"; TreeView1.Nodes.Add(node); // 添加根 AddTestNodes(node); //添加"展开..."节点 } } private void AddTestNodes(TreeNode node) { TreeNode testnode = new TreeNode(); testnode.Text = "正在展开...."; testnode.NodeData = "testnode"; node.Nodes.Add(testnode); } private void AddNodes(TreeNode node) { string parentID = "0"; if(node.Parent != null) { parentID = node.NodeData; }
// deeptree 为表名 string cmdstr = "select * from deeptree where parentid="+parentID; OleDbCommand cmd = new OleDbCommand(cmdstr,Con); try { Con.Open(); OleDbDataReader reader = cmd.ExecuteReader(); while(reader.Read()) { TreeNode childNode = new TreeNode(); childNode.Text = reader["content"].ToString(); childNode.NodeData = reader["id"].ToString(); //***************** 判断是否有子节点 ************ // // deeptree 为表名 cmdstr = "select count(*) from deeptree where parentid="+childNode.NodeData; OleDbConnection Con1 = new OleDbConnection(dataConStr); OleDbCommand cmd1 = new OleDbCommand(cmdstr,Con1); Con1.Open(); OleDbDataReader reader1 = cmd1.ExecuteReader(); if(reader1.Read()) { if(System.Convert.ToInt32(reader1[0]) > 0) { AddTestNodes(childNode); // 若有子节点,则添加测试节点 } } reader1.Close(); Con1.Close(); //************************************************* // node.Nodes.Add(childNode); } } catch(Exception ex) { Label3.Text = ex.Message; } finally { if(Con.State != ConnectionState.Closed) Con.Close(); } } #region Web 窗体设计器生成的代码 override protected void OnInit(EventArgs e) { // // CODEGEN: 该调用是 ASP.NET Web 窗体设计器所必需的。 // InitializeComponent(); base.OnInit(e); } /// <summary> /// 设计器支持所需的方法 - 不要使用代码编辑器修改 /// 此方法的内容。 /// </summary> private void InitializeComponent() { this.TreeView1.Expand += new Microsoft.Web.UI.WebControls.ClickEventHandler(this.TreeView1_Expand); this.Load += new System.EventHandler(this.Page_Load); } #endregion private void TreeView1_Expand(object sender, Microsoft.Web.UI.WebControls.TreeViewClickEventArgs e) { Label1.Text = e.Node; TreeNode node = new TreeNode(); node = TreeView1.GetNodeFromIndex(e.Node); //node = TreeView1.GetNodeFromIndex("0.2"); if(node != null) { Label2.Text = node.NodeData; // 判断该节点下子节点数,若1个且为testnode说明未填充所以子节点 if((node.Nodes.Count == 1)&& (node.Nodes[0].NodeData == "testnode")) { node.Nodes.Clear(); //清空 AddNodes(node); // 填充子节点 } } } } }
数据库中设置字段为 id, content,parentid PS: 缺点,因为AutoPostBack为TRUE,提交到服务器时每次都会闪烁. 而且载入数据越多越慢.. 没有 用ASP 来的快. 
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