How to implement logger in Excel?

Question

I'm trying to implement logger for Excel, which WONT logg user changes to cell values (who cares...).

But internal dynamics of my app.

So:

1. It must be sheet based. (Cause user wont be able to remember to attach some strange files from strange locations...)
2. It must be easily excel-able. (Excel is quite good at simple analytics, right? I do not want to write any custom parser for logs. Just use built in functionality of Excel)
3. It must be elastic, when sometimes I will log additonal info, sometimes those will be variables, sometimes arrays, objects, etc.

Q: How to handle 3)? ParamArray will treat incoming array as single element. While using Array/Collection require preprocessing of scalar values into one item arrays/collections when loggin.

Here is my code so far:

Public Sub Log(level As LoggerSeverityLevel, functionName As String, message As   String, Optional Arguments As Variant)
Dim sh As Object
Set sh = ActiveSheet

LoggerDB.Activate
''' Find blank row for next entry
Dim firstEmptyRow As LongLong
firstEmptyRow = Range("A" & rows.count).End(xlUp).row + 1

''' Parse level into human redable format
Dim lvlMessage As String
lvlMessage = "Unknown"
If level = lslInfo Then lvlMessage = "Info"
If level = lslWarning Then lvlMessage = "Warning"
If level = lslDebug Then lvlMessage = "Debug"
If level = lslCritical Then lvlMessage = "Critical"

''' Insert data
LoggerDB.Cells(firstEmptyRow, 1) = Now()
LoggerDB.Cells(firstEmptyRow, 2) = lvlMessage
LoggerDB.Cells(firstEmptyRow, 3) = functionName
LoggerDB.Cells(firstEmptyRow, 4) = message

''' And optional arguments, one cell per argument
Dim i As Long
Dim arg As Variant
i = 4
For Each arg In Arguments
    LoggerDB.Cells(firstEmptyRow, i) = CStr(arg)
    i = i + 1
Next arg

sh.Activate
End Sub

Answer 1

Public Sub Log(level As LoggerSeverityLevel, functionName As String, message As String,    Optional Arguments As Variant)
Dim sh As Object
Set sh = ActiveSheet

LoggerDB.Activate
''' Find blank row for next entry
Dim firstEmptyRow As LongLong
firstEmptyRow = Range("A" & rows.count).End(xlUp).row + 1

''' Parse level into human redable format
Dim lvlMessage As String
lvlMessage = "Unknown"
If level = lslInfo Then lvlMessage = "Info"
If level = lslWarning Then lvlMessage = "Warning"
If level = lslDebug Then lvlMessage = "Debug"
If level = lslCritical Then lvlMessage = "Critical"

''' Insert data
LoggerDB.Cells(firstEmptyRow, 1) = Now()
LoggerDB.Cells(firstEmptyRow, 2) = lvlMessage
LoggerDB.Cells(firstEmptyRow, 3) = functionName
LoggerDB.Cells(firstEmptyRow, 4) = message

''' And optional arguments, one cell per argument
Dim i As Long
Dim arg As Variant
i = 5
Dim tmp As Variant
Dim coll As Collection

This part pack scalars (number, string, bool, whatever single value) into collection. So I can always assume that if any additional arguments are passed, For Each will work.

It relay on TypeName() returning string with "()" for arrays.

If Not IsMissing(Arguments) Then ' If not iterable by for each (single variable) pack into collection. If Not (InStr(TypeName(Arguments), "()") <> 0 Or TypeName(Arguments) = "Collection" Or TypeName(Arguments) = "Dictionary") Then Set coll = New Collection coll.add Arguments Set tmp = coll Else tmp = Arguments End If

    For Each arg In tmp
        LoggerDB.Cells(firstEmptyRow, i) = CStr(arg)
        i = i + 1
    Next arg
End If

sh.Activate
End Sub