.NET (Core and Framework)

Private Sub CreateTree(ByVal TreeView As TreeView)
        Try
            Dim rootNode As New TreeNode(arr_Node(0).ToString)
            TreeView.BeginUpdate()
            TreeView.Nodes.Add(rootNode)

            intParentNode = 1
            AddChild(rootNode, arr_Node)
            TreeView.EndUpdate()
        Catch exc As Exception
            Throw exc
        End Try
    End Sub

    Private Sub AddChild(ByVal ParentNode As TreeNode, ByVal array() As String)
        Try
            If array.Length > intParentNode Then
                Dim ChildNode As New TreeNode(array(intParentNode))
                intParentNode += 1
                ParentNode.Nodes.Add(ChildNode)
                AddChild(ChildNode, array)
            End If
        Catch exc As Exception
            Throw exc
        End Try
    End Sub

<br />
    Public Sub AddItem(ByVal text As String, ByVal tree As TreeView)<br />
        Dim item As String<br />
        Dim node As TreeNode<br />
        Dim splitted As String() = text.Split(".")<br />
        Dim currentNodes As TreeNodeCollection = tree.Nodes<br />
<br />
        For Each item In splitted<br />
            node = GetNodeWithText(item, currentNodes)<br />
            If node Is Nothing Then<br />
                node = currentNodes.Add(item)<br />
            End If<br />
            currentNodes = node.Nodes<br />
        Next<br />
    End Sub<br />
<br />
    Private Function GetNodeWithText(ByVal text As String, ByVal nodes As TreeNodeCollection) As TreeNode<br />
        Dim node As TreeNode<br />
<br />
        For Each node In nodes<br />
            If node.Text = text Then<br />
                Return node<br />
            End If<br />
        Next<br />
<br />
        Return Nothing<br />
    End Function<br />