.NET平台下Web树形结构程序设计
.NET平台下Web树形结构程序设计
数据库设计
|
列名
|
数据类型
|
描述
|
长度
|
主键
|
|
ID
|
Int
|
节点编号
|
4
|
是
|
|
ParentID
|
Int
|
父节点编号
|
4
|
|
|
ConText
|
Nvarchar
|
我们要显示的节点内容
|
50
|
|
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',1)
insert tbtree (ID,Context,ParentID) values ( 3,'天津',1)
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 "-//W 3C //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