Public Class Form1
 
    Private Structure onoff
        Public makeon As Date
        Public makeoff As Date
        Public Sub New(ByVal _on As Date, ByVal _off As Date)
            makeon = _on
            makeoff = _off
        End Sub
    End Structure
    Private onofflist As New List(Of onoff)
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles MyBase.Load
        onofflist.Add(New onoff(New Date(1, 1, 1, 23, 0, 0), New Date(1, 1, 1, _
        1, 0, 0)))
        onofflist.Add(New onoff(New Date(1, 1, 1, 19, 0, 0, 0), New Date(1, 1, _
        1, 22, 30, 0)))
    End Sub
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button1.Click
        'erstmal sortieren
        onofflist.Sort(AddressOf sort_list)
        'jetzt vergleichen
        If istimeok(New Date(1, 1, 1, 22, 0, 0), New Date(1, 1, 1, 0, 0, 30)) _
          Then
            MessageBox.Show("Zeit OK")
        Else
            MessageBox.Show("Zeit nicht OK")
        End If
    End Sub
 
    Private Function sort_list(ByVal p1 As onoff, ByVal p2 As onoff)
        If p1.makeon.Ticks < p2.makeon.Ticks Then
            Return True
        Else
            Return False
        End If
    End Function
 
    Private Function istimeok(ByVal start As Date, ByVal finish As Date) As _
      Boolean
        For Each oo In onofflist
            'da die liste aller zeiten sortiert ist muss nur geprüft werden ob 
            ' die geprüfte zeit
            'innerhalb einer der anderen zeiten liegt
            If (start.Ticks > oo.makeon.Ticks And start.Ticks < _
              oo.makeoff.Ticks) Or _
               (finish.Ticks > oo.makeon.Ticks And finish.Ticks < _
               oo.makeoff.Ticks) Then
                Return False
                Exit Function
            End If
        Next
        Return True
    End Function
End Class