Question

我有四个级别的树视图;父母，孩子，孙子，曾孙。我的selectednode处于孙子级别。

我要做的是在孙子身上创建一个新的“Treeview” - 不，我不想为“selectednode”（孙子）创建一个新节点。所以它应该是这样的：

父儿童孙子（New TreeView）作为孙子的父母曾孙子曾孙子孙子孙子

这类似于父母的表格，母亲和父亲离开了，并且有一个新的孩子与另外一个配偶，而不是现有孩子的配偶。

   Private Sub PopulateRootLevel()
            ' query to find first round of parent
            PopulateNodes(dt, JCATreeView.Nodes)
    End Sub

Private Sub PopulateNodes(ByVal dt As DataTable, ByVal nodes As TreeNodeCollection)
        For Each dr As DataRow In dt.Rows
            Dim tn As New TreeNode()
            tn.Text = dr("TITLE").ToString()
            tn.Value = dr("Parent_ID").ToString()
            nodes.Add(tn)

            'If node has child nodes, then enable on-demand populating
            tn.PopulateOnDemand = (CInt(dr("childnodecount")) > 0)
        Next
End Sub

Private Sub PopulateSubLevel(ByVal parentid As Integer, ByVal parentNode As TreeNode)

        ' query to find children of parent with child node count of parent
         da.Fill(dt)
        PopulateNodes(dt, parentNode.ChildNodes)
End Sub

Protected Sub TreeView1_TreeNodePopulate(ByVal sender As Object, _
  ByVal e As System.Web.UI.WebControls.TreeNodeEventArgs) Handles TreeView1.TreeNodePopulate
        ' add a test to determine if this is from TreeView1 or Sub_TreeView1
         PopulateSubLevel(CInt(e.Node.Value), e.Node)
End Sub

Protected Sub TreeView1_SelectedNodeChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles TreeView1.SelectedNodeChanged

        Dim selected_parent_id As Integer = sender.SelectedNode.value
        Parent_to_NEW_TREEVIEW_PopulateSubLevel(selected_parent_id, sender.SelectedNode)
End Sub

Private Sub Sub_TreeView1_PopulateSubLevel(ByVal parent_id As Integer, ByVal parentNode As TreeNode)

        ' Query to get new children of parents
        da.Fill(dt2)
        Sub_TreeView1_PopulateNodes(dt2, parentNode.ChildNodes)
End Sub

    Private Sub Sub_TreeView1_PopulateNodes(ByVal dt As DataTable, ByVal nodes As TreeNodeCollection)
        For Each dr As DataRow In dt.Rows
            Dim tn As TreeNode = New TreeNode()
            'tn = parentBCNode.Nodes.Add("NEW_PARENT_TREEVIEW")

            ' query to get child on the new parent treeview

            tn.Text = dr("New parent title").ToString()
            tn.Value = dr("New_parent_ID").ToString()
            nodes.Add(tn)

            'If node has child nodes, then enable on-demand populating
            tn.PopulateOnDemand = (CInt(dr("childnodecount")) > 0)
        Next
    End Sub

Answer 1

你做不到。 TreeView不能将其另一个TreeView控件作为其子节点之一。您唯一能做的就是将TreeView分配给TreeNode的tag属性，但不会显示（显然）。我不明白你为什么要那样做，除非你想要那个孙子子树的不同绘图行为。您可以使用treeNode.Level属性来查找该节点所在的级别。您可以再次创建一个自定义对象（包含所有必需信息）并将其存储在treeNode.Tag属性中。

如何在所选节点添加新的树视图？

1 个答案: