Question

found a lot of questions involving finding duplicates in two columns :

i.e.
MS Excel how to create a macro to find duplicates and highlight them? and excel mark duplicates values

However I’m trying to adapt code to be used to find duplicates in one column. For example here is a data set:

Column 1

Foo
Bar
23
23
12
foo
Bar
bart

This is what I’m using right now:

Function warnDupes()

Dim lastRow As Long
Dim dict As Object

' Let Col be the column which warnDupes operates on.
Dim Col As String

Col = "A"

Set dict = CreateObject("scripting.dictionary")

lastRow = range(Col & Rows.Count).End(xlUp).Row

On Error Resume Next
For i = lastRow To 1 Step -1
    If dict.Exists(range(Col & i).value) = True Then

    'range("Y" & i).EntireRow.Delete

    MsgBox ("Hmm...Seems to be a duplicate of " & range(Col & i).value & _
    " in Cell " & Col & i)

End If
dict.Add range(Col & i).value, 1
Next

End Function

So far I’ve got some code that does 90% of the job. 23 and 23 are matched. Bar and Bar are matched. etc. So the code matches both Strings and Ints. But I’d like the macro to be able to match Foo and foo as a duplicate as well. How do I make Excel ignore case?

This question ( Function for detecting duplicates in Excel sheet ) seems relevent but I’m having trouble adapting the code or understanding what the author did. Any improvements to the code, explanations or suggestions would be very much appreciated.

Thanks.

UPDATE:

Just noticed something really weird.

The data:

IB6061
IC6071

are matched whether I use my Macro or if I use the Conditional Formatting tool in Excel. Any reason why?

Answer 1

On your Exists() & .Add() lines, make both values the same case:

If dict.Exists(UCase$(Range(Col & i).Value)) Then

and

dict.Add UCase$(Range(Col & i).Value), 1

That way the duplicates will always be added to the dictionary in uppercase and so case will never matter.