Dim wc As WindowContent
 
    Protected Sub erzeugen()
        ' Create Content which contains a RichTextBox
        Dim c As Content = _manager.Contents.Add(New RichTextBox, "RichTextBox")
 
        ' Request a new Docking window be created for the above Content on the 
        ' left edge
        If Not wc Is Nothing Then
            _manager.AddContentToWindowContent(c, wc)
        Else
            wc = _manager.AddContentWithState(c, State.DockLeft)
        End If
 
    End Sub