Tage Berechnung zwischen einem Bereich

Question

ich habe folgendes Problem

In einem bestimmten Bereich zum Beispiel 1. Januar 2017 zu 31. Januar 2017, Wie viele Tage des folgenden Bereichs Ereignisse Zeitraum aufgetreten?

Beispiel

1 range 1 Dec 2016/30 Jun 2017 = 31 
2 range 1 Jan 2017/2 Jan 2017 = 2 
3 range 4 Aug 2017/31 Aug 2017 = 0 
4 range 24 Sep 2015/2 Jan 2017 = 2 
5 range 6 Jan 2015/6 Feb 2016 = 0 

Haben Sie eine Idee für einen Algorithmus in access-VBA haben?

Vielen Dank

Answer 1

Public Function DaysInRange(vntRngStart As Date, vntRngEnd As Date, vntTestStart As Date, vntTestEnd As Date) As Integer 
On Error GoTo PROC_ERR 

    Dim vntOverlapStart As Date 
    Dim vntOverlapEnd As Date 

    If vntRngStart > vntRngEnd Then 
     MsgBox "Main date range is specified back-to-front, swap the dates and try again.", vbInformation, "Invalid input..." 
     DaysInRange = -1 
     Exit Function 
    ElseIf vntTestStart > vntTestEnd Then 
     MsgBox "Test date range is specified back-to-front, swap the dates and try again.", vbInformation, "Invalid input..." 
     DaysInRange = -2 
     Exit Function 
    End If 

    If vntTestEnd < vntRngStart Or vntTestStart > vntRngEnd Then 
     'Either your test range ends before the given range starts, 
     'or the test range starts after the end of the given range, 
     'so there is no overlap between the two ranges. 
     DaysInRange = 0 
     Exit Function 
    End If 

    'So now we know that there must be some overlap 
    If vntTestStart <= vntRngStart Then 
     'Our test range starts before the start of the given range, 
     'so the overlap starts at the beginning of the given range 
     vntOverlapStart = vntRngStart 
    Else 
     'Our test range starts after the start of the given range, 
     'so the overlap starts at the beginning of the test range 
     vntOverlapStart = vntTestStart 
    End If 
    If vntTestEnd >= vntRngEnd Then 
     'Our test range ends after the end of the given range, 
     'so the overlap ends at the end of the given range 
     vntOverlapEnd = vntRngEnd 
    Else 
     'Our test range ends after the end of the given range, 
     'so the overlap ends at the end of the test range 
     vntOverlapEnd = vntTestEnd 
    End If 
    DaysInRange = DateDiff("d", vntOverlapStart, vntOverlapEnd) + 1 

PROC_EXIT: 
    On Error Resume Next 
    Exit Function 

PROC_ERR: 
    MsgBox "Error " & Err.Number & " in Function 'DaysInRange': " & Err.Description 
    Resume PROC_EXIT 

End Function