VB Forum / General / November 2004

Look at the GlobalMultiUse attribute for classes and consider putting all
the classes into a single DLL. Then you only have to reference that DLL from
each project where you need at least one of those functions.

Classes should only be used when you're encapsulating some kind of data within the object, standalone methods should IMO be left in
standard code modules.  For instance if you have a FileFuncs class then you may want a method on there which goes and gets all the
files in a directory and stores them internally, then a Sort method on the class which sorts that data (still inside the class) and
finally an accessor that provides indexed access to the list of files.
A module based solution on the other hand would need one method that returns an array of all the files in a folder, then a second
function to sort an array of strings (more generic than putting the same functionality right into the first method) if you want you
could always write a wrapper function which returns a sorted list of files by calling both functions and returning the result.
If the sorting code resides in a different module than file listing code and you don't want to keep the reference between them then
you may want to look at using conditional compile arguments (Project -> Properties -> Make -> Conditional Compilation Arguments),
something like:

'*** modFiles.bas
Public Function GetFiles(ByRef inFolder As String) As String()
   ...
End Function

#If (UseModSort) Then ' Include method to get sorted file list
   Public Function GetSortedFiles(ByRef inFolder As String) As String()
       Dim RetArr() As String
       RetArr() = GetFiles(inFolder)
       Call SortStringArr(RetArr)
       GetSortedFiles = RetArr
   End Function
#End If
'***

'*** modSort.bas
Public Function SortStringArr(ByRef inArr() As String) As Boolean
   ...
End Function
'***

When you include the modSort module in your code then define the UseModSort conditional compile argument (UseModSort=1) and you'll
get access to the additional function in modFiles.
Using the class based approach you can do the same thing, keep the functionality in the module but add it to the class when it's
available:

'*** clsFiles.cls
Private m_Files() As String
Private m_NumFiles As Long

Public Property Get FileName(ByVal inIdx As Long) As String
   If ((inIdx >= 0) And (inIdx < m_NumFiles)) Then _
       FileName = m_Files(inIdx) ' Return file
End Property

Public Function GetFiles(ByRef inPath As String) As Long
   ... Populate m_Files() and m_NumFiles here..
End Function

#If (UseModSort) Then
   Public Sub Sort() ' Include sort functionality where available
       Call SortStringArr(m_Files())
   End Sub
#End If
'***

Hope this helps,

   Mike

- Microsoft Visual Basic MVP -
E-Mail: EDais@mvps.org
WWW: Http://EDais.mvps.org/