Public Overridable Property Reihe As cReihe(Of T)
            Get
                Return mReihe
            End Get
            Set(value As cReihe(Of T))
                ' einen Clone einfügen...
                value = value.Clone
 
                mReihe = value
            End Set
        End Property

   ' ein beliebiges Element
    Public Class Element
        Public Länge As Integer
        Public Breite As Integer
 
        Public Sub New(ByVal L As Integer, B As Integer)
            Me.Länge = L
            Me.Breite = B
        End Sub
    End Class
 
    ' generische Klasse
    Public Class cReihe(Of T As Element)
        Public Anzahl As Integer
        Public Element As T
 
        Public Overridable Function Clone() As cReihe(Of T)
            Dim R As New cReihe(Of T)
            R.Element = Me.Element
            R.Anzahl = Me.Anzahl
 
            Return R
        End Function
    End Class
 
    ' originale Klasse
    Public Class MyTestClass
        Inherits TestClass(Of Element)
 
        Public Overloads Property Reihe As MyReihe
            Get
                Return DirectCast(MyBase.Reihe, MyReihe)
            End Get
            Set(value As MyReihe)
                MyBase.Reihe = value
            End Set
        End Property
    End Class
 
    ' Abgeleitete Klasse
    Public Class MyReihe
        Inherits cReihe(Of Element)
 
        Public Breite As Integer
 
        Public Overloads Function Clone() As MyReihe
            Dim R As New MyReihe
            R.Element = Me.Element
            R.Anzahl = Me.Anzahl
            R.Breite = Me.Breite
 
            Return R
        End Function
    End Class
 
    ' abgeleitete Klasse
    Public Class TestClass(Of T As Element)
        Private mReihe As cReihe(Of T)
 
        Public Overridable Property Reihe As cReihe(Of T)
            Get
                Return mReihe
            End Get
            Set(value As cReihe(Of T))
                ' einen Clone einfügen...
                value = value.Clone
 
                mReihe = value
            End Set
        End Property
    End Class
 
    'Aufrufbeispiel
    Sub Test()
        Dim R As New MyReihe()
        R.Anzahl = 100
        R.Breite = 10
        R.Element = New Element(30, 60)
 
        Dim TC As New MyTestClass
        TC.Reihe = R
 
        Debug.Print(TC.Reihe.Breite.ToString)
    End Sub