Question

I want to have/define a unique id for each data row in my Excel data sheet – such that I can use it when passing the data onwards and it stays the same when rows are added/deleted above it.

My thoughts are to use the ID attribute of Range (msdn link)

So, I have a user defined function (UDF) which I place in each row that gets/sets the ID as follows:

Dim gNextUniqueId As Integer

Public Function rbGetId(ticker As String)
    On Error GoTo rbGetId_Error
    Dim currCell As Range
    'tried using Application.Caller direct, but gives same error
    Set currCell = Range(Application.Caller.Address)
    If currCell.id = "" Then
        gNextUniqueId = gNextUniqueId + 1
        'this line fails no matter what value I set it to.
        currCell.id = Str(gNextUniqueId)
    End If
    rbGetId = ticker & currCell.id
    Exit Function

    rbGetId_Error:
    rbGetId = "!ERROR:" & Err.Description
End Function

But this fails at the line mentioned with

“Application-defined or object-defined error”

I thought perhaps its one of those limitations of UDFs, but I also get the same error if I try it from code triggered from a ribbon button…

Any other suggestions on how to keep consistent ids – perhaps I should populate the cells via my ribbon button, finding cells without IDs and generating/setting the cell value of those…

EDIT:
As Ant thought, I have the sheet protected, but even in an unlocked cell it still fails. Unprotecting the sheet fixes the problem…. but I have used “Protect UserInterFaceOnly:=True” which should allow me to do this. If I manually allow “Edit Objects” when I protect the sheet it also works, but I don’t see a programmatic option for that – and I need to call the Protect function in AutoOpen to enable the UserInterfaceOnly feature…

I guess I need to turn off/on protect around my ID setting – assuming that can be done in a UDF… which it seems it cannot, as that does not work – neither ActiveSheet.unprotect nor ActiveWorkbook.unprotect 🙁

Thanks in advance.
Chris

Answer 1

I have found that if I protect the sheet with “Protect DrawingObjects:=False”, the UDF can set the Id. Strange.

Thanks for all the help with this.