Dim bag As New System.Collections.Generic.Dictionary(Of DayOfWeek, List(Of _
  DateTime))()
 
Dim dt As DateTime = New DateTime(2008, 1, 1).AddDays(-1)
Dim monat As Integer = dt.Month
While dt.Month.Equals(monat)
	dt = dt.AddDays(1)
	Dim wochenTagListe As List(Of DateTime) = bag(dt.DayOfWeek)
	If wochenTagListe Is Nothing Then
		wochenTagListe = New List(Of DateTime)()
		bag.Add(dt.DayOfWeek, wochenTagListe)
	End If
	wochenTagListe.Add(dt)
End While
 
Dim AnzahlMontage As Integer = bag(DayOfWeek.Monday).Count