' Ein Stuktur erstellen in der man ein Objekt speichern kann.
Public Structure ClassInstance
 
    Private _instance As Object
 
    Public Sub New(ByVal instance As Object)
 
        _instance = Instace
 
    End Sub
    Public ReadOnly Property Instace() As Object
        Get
            Return _instance
        End Get
    End Property
 
End Structure
 
Public Class Class1
 
End Class
 
Public Class Class2
 
End Class
 
Public Class Instance
 
    ' Diesmal ein Dictionary, dies erleichtert das auffinden der Instanzen, da 
    ' jede ihren eigenen      Namen hat.
    Private _dictionary As New Dictionary(Of String, ClassInstance)
 
    ' Erzeugen der Instanz und den Dictionary anfügen
    Public Sub Add(ByVal key As String, ByVal instanceType As String)
 
        Select Case instanceType
            Case "Class1"
                _dictionary.Add(key, CType(New ClassInstance(), Object))
                ' .....
        End Select
 
    End Sub
 
    ' Klass1 Instanzen zurückgeben und wenn nötig wieder speichern
    Public Property Class1Instance(ByVal key As String) As Class1
        Get
 
            For Each kvp As KeyValuePair(Of String, ClassInstance) In _
              _dictionary
                If kvp.Key = key Then
                    Return CType(kvp.Value.Instace, Class1)
                End If
            Next
 
            Throw New Exception("KeyNotFound")
 
        End Get
        Set(ByVal value As Class1)
            _dictionary.Remove(key)
            _dictionary.Add(key, New ClassInstance(CType(value, Object)))
        End Set
    End Property
 
    ' Klass2 Instanzen zurückgeben und wenn nötig wieder speichern
    Public Property Class2Instance(ByVal key As String) As Class2
        Get
 
            For Each kvp As KeyValuePair(Of String, ClassInstance) In _
              _dictionary
                If kvp.Key = key Then
                    Return CType(kvp.Value.Instace, Class2)
                End If
            Next
 
            Throw New Exception("KeyNotFound")
 
        End Get
        Set(ByVal value As Class2)
            _dictionary.Remove(key)
            _dictionary.Add(key, New ClassInstance(CType(value, Object)))
        End Set
    End Property
 
End Class