Private Sub Form_Load()
MsgBox DateDiffW(Date, CDate("01/12/2007")), , "Верну число рабочих дней, оставшихся до 1 декабря"
End Sub

Function DateDiffW(BegDate, EndDate)
Const SUNDAY = 1
Const SATURDAY = 7
Dim NumWeeks As Integer

If BegDate > EndDate Then
DateDiffW = 0
Else
Select Case Weekday(BegDate)
Case SUNDAY: BegDate = BegDate + 1
Case SATURDAY: BegDate = BegDate + 2
End Select
Select Case Weekday(EndDate)
Case SUNDAY: EndDate = EndDate - 2
Case SATURDAY: EndDate = EndDate - 1
End Select
NumWeeks = DateDiff("ww", BegDate, EndDate)
DateDiffW = NumWeeks * 5 + Weekday(EndDate) - Weekday(BegDate)
End If
End Function

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