Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As _
  System.EventArgs) Handles Button3.Click
 
        Dim data = TextBox1.Text
        Dim arrLines = Split(data, vbNewLine)
 
 
        Dim strTree = "treeView1."
        Dim strNode = "Nodes"
        Dim strAdd = "add"
 
        Dim strLineParent = ""
        Dim strLineChilds = ""
        Dim node = ""
 
 
        TreeView1.BeginUpdate()
 
        For Each line As String In arrLines
            Dim arrLine = Split(line, ";")
            Dim arrNode = Split(arrLine(0), ",")
 
 
            If arrNode(0) = "" Then
                strLineParent = strTree & strNode & "." & strAdd & "(" & _
                  """Parent"")" & vbNewLine
                TextBox2.Text += strLineParent
            Else
                For Each node In arrNode
                    strLineChilds += strNode & "(" & node & ")."
                Next
                TextBox2.Text += strTree & strLineChilds & strNode & "." & _
                  strAdd & "(""" & arrLine(1) & """)" & vbNewLine
                strLineChilds = ""
            End If
        Next
 
        TreeView1.EndUpdate()
 
    End Sub