专栏作品
.NET平台下Web树形结构程序设计
李洪根
李洪根
CREATE TABLE [dbo].[tbTree] ( [ID] [int] IDENTITY (1, 1) NOT NULL , [Context] [nvarchar] (50) COLLATE Chinese_PRC_CI_AS NULL , [ParentID] [int] NULL ) ON [PRIMARY]
SET IDENTITY_INSERT tbtree ON insert tbtree (ID,Context,ParentID) values ( 1,'中国',0) insert tbtree (ID,Context,ParentID) values ( 2,'北京',11) insert tbtree (ID,Context,ParentID) values ( 3,'天津',11) insert tbtree (ID,Context,ParentID) values ( 4,'河北省',1) insert tbtree (ID,Context,ParentID) values ( 5,'广东省',1) insert tbtree (ID,Context,ParentID) values ( 6,'广州',5) insert tbtree (ID,Context,ParentID) values ( 7,'四川省',1) insert tbtree (ID,Context,ParentID) values ( 8,'成都',7) insert tbtree (ID,Context,ParentID) values ( 9,'深圳',5) insert tbtree (ID,Context,ParentID) values ( 10,'石家庄',4) insert tbtree (ID,Context,ParentID) values ( 11,'辽宁省',1) insert tbtree (ID,Context,ParentID) values ( 12,'大连',11) insert tbtree (ID,Context,ParentID) values ( 13,'上海',1) insert tbtree (ID,Context,ParentID) values ( 14,'天河软件园',6) insert tbtree (ID,Context,ParentID) values ( 15,'汕头',5) SET IDENTITY_INSERT tbtree off
<%@ Register TagPrefix="iewc" Namespace="Microsoft.Web.UI.WebControls" Assembly="Microsoft.Web.UI.WebControls, Version=1.0.2.226, Culture=neutral, PublicKeyToken=31bf3856ad364e35" %>
<%@ Page Language="vb" AutoEventWireup="false" Codebehind="WebForm1.aspx.vb" Inherits="Tree.WebForm1"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<title>WebForm1</title>
<meta name="GENERATOR" content="Microsoft Visual Studio .NET 7.0">
<meta name="CODE_LANGUAGE" content="Visual Basic 7.0">
<meta name="vs_defaultClientScript" content="JavaScript">
<meta name="vs_targetSchema" content="http://schemas.microsoft.com/intellisense/ie5">
</HEAD>
<body MS_POSITIONING="GridLayout">
<form id="Form1" method="post" runat="server">
<FONT face="宋体">
<iewc:TreeView id="TreeView1" style="Z-INDEX: 101; LEFT: 39px; TOP: 68px" runat="server"></iewc:TreeView></FONT>
</form>
</body>
</HTML>
Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim ds As New DataSet()
Dim CN As 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()
Dim adp As SqlDataAdapter = New SqlDataAdapter("select * from tbTree", CN)
adp.Fill(ds)
Me.ViewState("ds") = ds
Catch ex As Exception
#If DEBUG Then
Session("Error") = ex.ToString()
Response.Redirect("error.aspx") '̀跳转程序的公共错误处理页面
#End If
Finally
'关闭连接
CN.Close()
End Try
'调用递归函数，完成树形结构的生成
AddTree(0, Nothing)
End Sub
'递归添加树的节点
Private Sub AddTree(ByVal ParentID As Integer, ByVal pNode As TreeNode)
Dim ds As DataSet
ds = Me.ViewState("ds")
Dim dvTree As New DataView()
dvTree = New DataView(ds.Tables(0))
'过滤ParentID,得到当前的所有子节点
dvTree.RowFilter = "PARENTID = " + ParentID.ToString
Dim Row As DataRowView
For Each Row In dvTree
Dim Node As New TreeNode()
If pNode Is Nothing Then '判断是否根节点
'添加根节点
Node.Text = Row("ConText").ToString()
TreeView1.Nodes.Add(Node)
Node.Expanded = True
'再次递归
AddTree(Int32.Parse(Row("ID").ToString()), Node)
Else
'̀添加当前节点的子节点
Node.Text = Row("ConText").ToString()
pNode.Nodes.Add(Node)
Node.Expanded = True
'再次递归
AddTree(Int32.Parse(Row("ID").ToString()), Node)
End If
Next
End Sub
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
{
///
/// WebForm1 的摘要说明
///
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"];
DataView dvTree = new DataView(ds.Tables[0]);
//过滤ParentID,得到当前的所有子节点
dvTree.RowFilter = "[PARENTID] = " + ParentID;
foreach(DataRowView Row in dvTree)
{
TreeNode Node=new TreeNode() ;
if(pNode == null)
{ //添加根节点
Node.Text = Row["ConText"].ToString();
TreeView1.Nodes.Add(Node);
Node.Expanded=true;
AddTree(Int32.Parse(Row["ID"].ToString()), Node); //再次递归
}
else
{ //̀添加当前节点的子节点
Node.Text = Row["ConText"].ToString();
pNode.Nodes.Add(Node);
Node.Expanded = true;
AddTree(Int32.Parse(Row["ID"].ToString()),Node); //再次递归
}
}
}
#region Web Form Designer generated code
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.Load += new System.EventHandler(this.Page_Load);
}
#endregion
}
}
