Public Sub PopulateNodes(ByVal nodes As TreeNodeCollection, Optional ByVal intParentID As Int32 = 0)
Dim showmenu As New ClassLibrary.Jkdata.JkDataBasic ‘创建一个新的类对象
Dim dt As New DataTable()
dt = showmenu.GetProduct_Class ‘获得业务层返回的datatable
Dim strExpression As String
strExpression = "[UpID] = " & intParentID
Dim foundRows() As DataRow
foundRows = dt.Select(strExpression)
Dim I As Integer
Dim PassID As Integer
For I = 0 To foundRows.GetUpperBound(0)
Dim tn As New TreeNode()
tn.Text = foundRows(I).Item("ClassName").ToString()
tn.Value = foundRows(I).Item("ID").ToString()
If foundRows(I).Item("UpID") = 0 Then
tn.NavigateUrl = foundRows(I).Item("Url").ToString‘父分类的页面连接
Else
PassID = Convert.ToInt32(foundRows(I).Item("ID"))
tn.NavigateUrl = foundRows(I).Item("Url") + "?classid=" + PassID.ToString ‘子分类的页面连接含参数传递

End If

Dim dr() As DataRow
dr = dt.Select("[UpID] = " & tn.Value)
If dr.GetUpperBound(0) > -1 Then
tn.PopulateOnDemand = True
End If
nodes.Add(tn)
Next
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

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