Datoer går igennem denne måned

'Start date is before 01/08/12
blnStartsBefore = DateDiff("d", startDate, Date("01/08/12")) >= 0

'End date is after 01/08/12
blnEndsAfter = DateDiff("d", Date("01/08/12"), endDate) >= 0

If blnStartsBefore AND blnEndsAfter Then
   'Do your magic
End If

' Check if start date is before end date
blnBeginsBeforeEnding = DateDiff("d", startDate, endDate) > 0

' Check if start date is before the end of August
blnBeginsBeforeAugEnds = DateDiff("d", startDate, Date("31/08/12")) >= 0

'Check if the end date is after the beginning of August
blnEndsAfterAugBegins = DateDiff("d", Date("01/08/12"), endDate) >= 0

' Holds whether or not the timespan intersects August
blnIntersectsAug = False

If NOT blnBeginsBeforeEnding Then
   ' Check if start date and end date are the same
   If DateDiff("d", startDate, endDate) = 0 Then

      ' If the start date is in August, the timespan intersects August
      blnIntersectsAug = blnBeginsBeforeAugEnds
   Else
      ' Handle invalid timespan
   End If
Else If blnBeginsBeforeAugEnds AND blnEndsAfterAugBegins Then
   blnIntersectsAug = True
End If

If blnIntersectsAug Then
   ' Do your magic here
End If

Function CheckForMonthIntersect(dtmBegin, dtmEnd, intYear, intMonth)
   ' Holds the first day of the month
   dtmMonthBegin = DateSerial(intYear, intMonth, 1)

   'Holds the last day of the month
   dtmMonthEnd = DateSerial(intYear, intMonth + 1, 0)

   ' Check if start date is before end date
   blnBeginsBeforeEnding = DateDiff("d", dtmBegin, dtmEnd) > 0

   ' Check if start date is before the end of August
   blnBeginsBeforeAugEnds = DateDiff("d", dtmBegin, dtmMonthEnd) >= 0

   'Check if the end date is after the beginning of August
   blnEndsAfterAugBegins = DateDiff("d", dtmMonthBegin, dtmEnd) >= 0

   ' Holds whether or not the timespan intersects August
   blnIntersectsAug = False

   If NOT blnBeginsBeforeEnding Then
      ' Check if start date and end date are the same
      If DateDiff("d", dtmBegin, dtmEnd) = 0 Then

         ' If the start date is in August, the timespan intersects August
         CheckForMonthIntersect = blnBeginsBeforeAugEnds
         Exit Function
      Else
         ' The timespan is invalid, so no check can be made
         CheckForMonthIntersect = False
         Exit Function
      End If
   Else If blnBeginsBeforeAugEnds AND blnEndsAfterAugBegins Then
      CheckForMonthIntersect = True
   End If
End Function

if month(startdato) <= 8 _
   and month(slutdato) >= 8 _
   and year(startdato) <= year(slutdato) _
then
  ' intervallet krydser august
else
  ' intervallet krydser ikke august
end if

function KrydserMaaned(startdato, slutdato, maaned)
   KrydserMaaned = month(startdato) <= maaned _
                   and month(slutdato) >= maaned _
                   and year(startdato) <= year(slutdato)
end function