ASP.NET 2005 Treeview终极解决方案

Public Function GetTreeTable() As DataTable

　　　Dim dt As New DataTable()

　　　dt = HttpContext.Current.Cache("Treeview")

　　　If dt Is Nothing Then

　　Dim Conn As New SqlConnection

　　Dim clsConnDatabase As New ConnectionDatabase

　　Conn = clsConnDatabase.ConnDatabase

　　Dim Command As New SqlCommand

　　Command.Connection = Conn

　　Command.CommandText = "GetTreeview"

　　Command.CommandType = CommandType.StoredProcedure

　　Command.ExecuteNonQuery()

　　Dim da As New SqlDataAdapter(Command)

　　dt = New DataTable()

　　da.Fill(dt)

　　HttpContext.Current.Cache.Insert("Treeview", dt)

　　　End If

　　　Return dt

　　End Function

　　这里是主要阿

　　Public Sub PopulateNodes(ByVal nodes As TreeNodeCollection, Optional ByVal intParentID As Int32 = 0)

　　　Dim dt As New DataTable()

　　　dt = clsWebForms.GetTreeTable()

　　　Dim strExpression As String

　　　strExpression = "[parentID] = " & intParentID

　　　Dim foundRows() As DataRow

　　　foundRows = dt.Select(strExpression)

　　　

　　　Dim I As Integer

　　　For I = 0 To foundRows.GetUpperBound(0)

　　Dim tn As New TreeNode()

　　tn.Text = foundRows(I).Item(“TableName”).ToString()

　　tn.Value = foundRows(I).Item("ID").ToString()

　　Dim dr() As DataRow

　　dr = dt.Select("[parentID] = " & tn.Value)

　　If dr.GetUpperBound(0) > -1 Then

　　　tn.PopulateOnDemand = True

　　End If

　　nodes.Add(tn)

　　　Next

　　End Sub

　　建立WebForm 放入Treeview

　　Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

　　　　　

　　　If Not Page.IsPostBack Then

　　PopulateNodes(TreeView1.Nodes, 0)

　　　End If

　　End Sub

　　Protected Sub TreeView1_TreeNodePopulate(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.TreeNodeEventArgs) Handles TreeView1.TreeNodePopulate

　　　PopulateNodes(e.Node.ChildNodes, e.Node.Value)

　　End Sub