日期:2011-03-26  浏览次数:20388 次

 这几天在写HRM的时候 这问题搞了我两天,开始在使用Google 找了半天都是一堆垃圾,都是使用算法的较多, 后来就去了的msdn.yesky.com 找到点启示。 好了废话多说无用。

  首先表结构如下 表名 Test


  写个存储过程 GetTreeview

  这个不用我说了吧下面用到

  为了速度缓存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

  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

  至于速度我没测试,如果大家有兴趣帮忙测测。