How to normalize filenames listed in a range - vba

Question

I have a list of filenames in a spreadsheet in the form of "Smith, J. 010112.pdf". However, they're in the varying formats of "010112.pdf", "01.01.12.pdf", and "1.01.2012.pdf". How could I change these to one format of "010112.pdf"?

Answer 1

Personally I hate using VBA where worksheet functions will work, so I've worked out a way to do this with worksheet functions. Although you could cram this all into one cell, I've broken it out into a lot of independent steps in separate columns so you can see how it's working, step by step.
For simplicity I'm assuming your file name is in A1
B1 =LEN(A1)
determine the length of the filename
C1 =SUBSTITUTE(A1," ","")
replace spaces with nothing
D1 =LEN(C1)
see how long the string is if you replace spaces with nothing
E1 =B1-D1
determine how many spaces there are
F1 =SUBSTITUTE(A1," ",CHAR(8),E1)
replace the last space with a special character that can't occur in a file name
G1 =SEARCH(CHAR(8), F1)
find the special character. Now we know where the last space is
H1 =LEFT(A1,G1-1)
peel off everything before the last space
I1 =MID(A1,G1+1,255)
peel off everything after the last space
J1 =FIND(".",I1)
find the first dot
K1 =FIND(".",I1,J1+1)
find the second dot
L1 =FIND(".",I1,K1+1)
find the third dot
M1 =MID(I1,1,J1-1)
find the first number
N1 =MID(I1,J1+1,K1-J1-1)
find the second number
O1 =MID(I1,K1+1,L1-K1-1)
find the third number
P1 =TEXT(M1,"00")
pad the first number
Q1 =TEXT(N1,"00")
pad the second number
R1 =TEXT(O1,"00")
pad the third number
S1 =IF(ISERR(K1),M1,P1&Q1&R1)
put the numbers together
T1 =H1&" "&S1&".pdf"
put it all together
It's kind of a mess because Excel hasn't added a single new string manipulation function in over 20 years, so things that should be easy (like "find last space") require severe trickery.

Answer 2

Here's a screenshot of a simple four-step method based on Excel commands and formulas, as suggested in a comment to the answered post (with a few changes)...

Answer 3

This function below works. I've assumed that the date is in ddmmyy format, but adjust as appropriate if it's mmddyy -- I can't tell from your example.
Function FormatThis(str As String) As String
Dim strDate As String
Dim iDateStart As Long
Dim iDateEnd As Long
Dim temp As Variant
' Pick out the date part
iDateStart = GetFirstNumPosition(str, False)
iDateEnd = GetFirstNumPosition(str, True)
strDate = Mid(str, iDateStart, iDateEnd - iDateStart + 1)
If InStr(strDate, ".") <> 0 Then
' Deal with the dot delimiters in the date
temp = Split(strDate, ".")
strDate = Format(DateSerial( _
CInt(temp(2)), CInt(temp(1)), CInt(temp(0))), "ddmmyy")
Else
' No dot delimiters... assume date is already formatted as ddmmyy
' Do nothing
End If
' Piece it together
FormatThis = Left(str, iDateStart - 1) _
& strDate & Right(str, Len(str) - iDateEnd)
End Function
This uses the following helper function:
Function GetFirstNumPosition(str As String, startFromRight As Boolean) As Long
Dim i As Long
Dim startIndex As Long
Dim endIndex As Long
Dim indexStep As Integer
If startFromRight Then
startIndex = Len(str)
endIndex = 1
indexStep = -1
Else
startIndex = 1
endIndex = Len(str)
indexStep = 1
End If
For i = startIndex To endIndex Step indexStep
If Mid(str, i, 1) Like "[0-9]" Then
GetFirstNumPosition = i
Exit For
End If
Next i
End Function
To test:
Sub tester()
MsgBox FormatThis("Smith, J. 01.03.12.pdf")
MsgBox FormatThis("Smith, J. 010312.pdf")
MsgBox FormatThis("Smith, J. 1.03.12.pdf")
MsgBox FormatThis("Smith, J. 1.3.12.pdf")
End Sub
They all return "Smith, J. 010312.pdf".

Answer 4

You don't need VBA. Start by replacing the "."s with nothing:
=SUBSTITUTE(A1,".","")
This will change the ".PDF" to "PDF", so let's put that back:
=SUBSTITUTE(SUBSTITUTE(A1,".",""),"pdf",".pdf")

Answer 5

Got awk? Get the data into a text file, and
awk -F'.' '{ if(/[0-9]+\.[0-9]+\.[0-9]+/) printf("%s., %02d%02d%02d.pdf\n", $1, $2, $3, length($4) > 2 ? substr($4,3,2) : $4); else print $0; }' your_text_file
Assuming the data are exactly as what you described, e.g.,
Smith, J. 010112.pdf
Mit, H. 01.02.12.pdf
Excel, M. 8.1.1989.pdf
Lec, X. 06.28.2012.pdf

Answer 6

DISCLAIMER:
As #Jean-FrançoisCorbett has mentioned, this does not work for "Smith, J. 1.01.12.pdf". Instead of reworking this completely, I'd recommend his solution!
Option Explicit
Function ExtractNumerals(Original As String) As String
'Pass everything up to and including ".pdf", then concatenate the result of this function with ".pdf".
'This will not return the ".pdf" if passed, which is generally not my ideal solution, but it's a simpler form that still should get the job done.
'If you have varying extensions, then look at the code of the test sub as a guide for how to compensate for the truncation this function creates.
Dim i As Integer
Dim bFoundFirstNum As Boolean
For i = 1 To Len(Original)
If IsNumeric(Mid(Original, i, 1)) Then
bFoundFirstNum = True
ExtractNumerals = ExtractNumerals & Mid(Original, i, 1)
ElseIf Not bFoundFirstNum Then
ExtractNumerals = ExtractNumerals & Mid(Original, i, 1)
End If
Next i
End Function
I used this as a testcase, which does not correctly cover all your examples:
Sub test()
MsgBox ExtractNumerals("Smith, J. 010112.pdf") & ".pdf"
End Sub