Public Class zufallsgenerator
    Private _zufall_gen As Object
    Private Shared _singleton As zufallsgenerator
    Public Shared Function getinstance() As zufallsgenerator
               If _singleton Is Nothing Then
        _singleton = New zufallsgenerator
                End If
        Return _singleton
    End Function
 
    Private Sub New()
        Me._zufall_gen = New Random(Environment.TickCount)
    End Sub
 
    Public Function erstell(ByVal untergrenze As Int64, ByVal obergrenze As _
      Int64) As Int64
        Return Me._zufall_gen.next(untergrenze, obergrenze + 1)
    End Function
End Class