VBScript keep last 14 files, delete anything older then 14 days - vbscript

Question

i have a VB Script file that goes thru many files and folders within a specific directopry path, and it deletes any files thats older then 30 days
but i want to add an exception, to keep the last 14 files, so lets say if i dont have any new files yesterday, then today it will delete the file older then 14 days, and i will be left with 13 files
i want to keep the last 14 files, no matter of its age, but if there is more then 14 files, then delete the oldest
can anyone assist me where i add it in my script, and how ? here is the script im using
On Error Resume Next
Set oFileSys = WScript.CreateObject("Scripting.FileSystemObject")
sRoot = "C:\Program Files (x86)\Syslogd\Logs" 'Path root to look for files
today = Date
nMaxFileAge = 14 'Files older than this (in days) will be deleted
DeleteFiles(sRoot)
Function DeleteFiles(ByVal sFolder)
Set oFolder = oFileSys.GetFolder(sFolder)
Set aFiles = oFolder.Files
Set aSubFolders = oFolder.SubFolders
For Each file in aFiles
dFileCreated = FormatDateTime(file.DateCreated, "2")
If DateDiff("d", dFileCreated, today) > nMaxFileAge Then
file.Delete(True)
End If
Next
For Each folder in aSubFolders
DeleteFiles(folder.Path)
Next
End Function

Answer 1

I think you could do this a few ways. One would be to use the DIR command to sort the files and then you can just iterate that list and delete the ones starting at the 15th position. For example, this command would return just the filenames, sorted by date in descending order:
dir /o-d /a-d /b
and you could run that using Shell.Run or Shell.Exec to capture its output. The "problem" with Shell.Run is that you'd need to send the output to a file, then open the file, and read it. Not a big deal but requires file I/O. If you use Shell.Exec, you can capture the standard output directly but you have to deal with the command prompt window flashing open whenever a DIR command runs.
If you're fine with either of those "problems", then that method should work fine.
But you could do everything using the FileSystemObject. The key is to just get the date of the 14th most-recent file. Here's how you could do that.
' Only run if we actually have more than 14 files...
If oFolder.Files.Count > 14 Then
' Create an array to the hold the dates of each file in this folder...
ReDim a(oFolder.Files.Count - 1)
' Store the dates...
i = 0
For Each oFile In oFolder.Files
a(i) = oFile.DateLastModified ' Or use DateCreated, if you wish
i = i + 1
Next
' Sort the array...
Sort a
' Get the 14th most-recent date...
dtmCutOff = a(13)
' Iterate the files once more and delete any files older than our cut-off...
For Each oFile In oFolder.Files
If oFile.DateLastModified < dtmCutOff Then oFile.Delete
Next
End If
' Simple bubble sort...
Sub Sort(a)
For i = UBound(a) - 1 To 0 Step -1
For j = 0 To i
If a(j) > a(j + 1) Then
temp = a(j + 1)
a(j + 1) = a(j)
a(j) = temp
End If
Next
Next
End Sub
The only issue I think you'll have is if two files with the exact same date and time occupy the 14th position. Using this method, the script would keep both, and you'd end up with 15 files (or more, if there were more matches). But that's going to be an issue no matter what method you use. If your 20 most-recent files have the same date and time, how you do choose 14 from amongst those 20 to keep? =)