Public Class frmEditList
 
    Dim WithEvents btnUndo As New Button With _
        {.Parent = Me, .Text = "UNDO", .Width = 100}
 
    Dim WithEvents btnRedo As New Button With _
        {.Parent = Me, .Text = "REDO", .Width = 100, .Left = 105}
 
    Dim rtb As New RichTextBox With _
        {.Parent = Me, .Top = 40, .Width = 400, .Height = 400, _
         .ScrollBars = RichTextBoxScrollBars.Both}
 
 
    Private Sub frmEditList_Load(sender As System.Object, _
                         e As System.EventArgs) Handles MyBase.Load
 
        Me.FormBorderStyle = _
           Windows.Forms.FormBorderStyle.Fixed3D
 
        Me.Size = New Size(410, 470)
    End Sub
 
 
    Public Property ListToEdit() As List(Of String)
        Set(value As List(Of String))
            Me.Refresh()
            rtb.Clear()
            rtb.Lines = value.ToArray
        End Set
        Get
            Return New List(Of String)(rtb.Lines)
        End Get
    End Property
 
 
    Private Sub btnRedo_Click(sender As Object, _
        e As System.EventArgs) Handles btnRedo.Click
        rtb.Redo()
    End Sub
 
    Private Sub btnUndo_Click(sender As Object, _
        e As System.EventArgs) Handles btnUndo.Click
        rtb.Undo()
    End Sub
End Class

 Public Class frmEditListDemo
 
    Dim texte As New List(Of String)
 
    Dim WithEvents btnEdit As New Button With _
        {.Parent = Me, .Text = "Edit"}
 
    Dim lboText As New ListBox With _
        {.Parent = Me, .Width = 400, .Height = 400, .Top = 40}
 
 
    Private Sub frmEditListDemo_Load(sender As System.Object, _
        e As System.EventArgs) Handles MyBase.Load
 
        Me.Size = New Size(410, 470)
        Me.DoubleBuffered = True 'eventuell
 
        'Demodaten
        For i As Integer = 0 To 1000
            texte.Add("Abschnitt " & (i + 1).ToString)
            texte.Add("Eine Textzeile ohne Informationsgehalt")
            texte.Add _
             ("Noch eine Zeile, die keine nützlichen Angaben enthält")
        Next i
 
        'Datenbindung erstellen
        lboText.DataSource = texte
    End Sub
 
 
    Private Sub btnEdit_Click(sender As Object, _
        e As System.EventArgs) Handles btnEdit.Click
 
        Me.Text = "Edit wird geöffnet ..."
        Me.Enabled = False
        Me.Refresh()
 
        'Edit-Dialog
        Using edit As New frmEditList
            'Liste an Edit-Form übergeben
            edit.ListToEdit = texte
 
            edit.ShowDialog()
 
            Me.Text = "Edit wird geschlossen ..."
            Me.Refresh()
 
            'Liste abfragen
            texte = edit.ListToEdit
        End Using
 
        'Datenbindung erneuern
        With lboText
            .SuspendLayout() 'eventuell
            .DataSource = texte
            .ResumeLayout()
        End With
 
        Me.Text = Me.Name
        Me.Enabled = True
    End Sub
End Class