ASP.NET 2005 Treeview終極解決方案

　這幾天在寫HRM的時候 這問題搞了我兩天，開始在使用Google 找了半天都是一堆垃圾，都是使用演算法的較多， 後來就去了的msdn.yesky.com 找到點啟示。 好了廢話多說無用。

　　首先表結構如下 表名 Test


　　寫個預存程序 GetTreeview

　　這個不用我說了吧下面用到

　　為了速度緩衝DataTable

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 　　這裡是主要阿 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

　　至於速度我沒測試，如果大家有興趣幫忙測測。