Conditionally Displaying a Message Box

@Chuck Trese: Thanks
@Alan Elston: Didn't know about Intersect - new knowledge always appreciated!

@ Chuck Trese
Nice clear explanation :-)

@ Ruthie A. Ward
Are you aware that Target is the selected / changed range? – Effectively, “behind the scenes” , when a change occurs anywhere in a Worksheet, then VBA does something pseudo like this
Set Target = range of cells changed

I could not quite follow what you were proposing

Alan Elston

regarding below post...
Of course, Range("C3") can be replaced with any range (single cell, contiguous cells, non-contiguous cells, named range, union, intersection, ......) to suit your needs.

Ok, maybe an explanation is called for here:
If Not Intersect(Target, Range("C3")) Is Nothing Then

I first saw this somewhere on the internet years ago, been using it ever since.
The "Target" range is the cells selected by the user at the time of the change event.
The Intersect function will give you the intersection (overlap) between two ranges.
If the two do not overlap, then the intersection will be Nothing.
If the Intersection is Not Nothing, then there is an intersection, which means cell C3 is somewhere within the Target range.
That would mean cell C3 was just changed.

This works regardless of the shape of the Target range.
pretty cool, eh?

@ Ruthie,
It's actually a LOT easier than that. You can use this construct:

Private Sub Worksheet_Change(ByVal Target As Range)
If Not Intersect(Target, Range("C3")) Is Nothing Then
MsgBox "Changed It!"
End If
End Sub

If you want to check a specific range, adding a loop to check each cell's address against the target address should work. To check non-specific ranges, select the desired ranges and use the loop to check each cell's address against your target address. In this case, the message box would only display if the cell with the target address is selected. If you combined the two looping checks, you could determine whether or not the target cell was changed with one macro and two nested IF statements. (I'm not good writing loop structures so ... indicates where they should go.)

Private Sub Worksheet_Change(ByVal Target As Range)
' Check loop specific.
...loop specific range
If Target.Address = "$C$3" Then
MsgBox "Changed It!"
Else
' Check if range is non-specific
If ...code to check selected range <> specific range
' Check loop non-specific
...loop non-specific
If Target.Address = $C$3" Then
MsgBox "Changed It!"
End If
...end loop non-specific
End If 'range check
End If
...end loop specific
End Sub

I need to display a message when any cell of a specific range of adjacent cells is changed. Is there any means of doing this by altering the code presented in this tip?
Thanks in advance...

I believe (although I did not experiment to confirm this) that this technique will not respond when the change is to a range of cells. If, for instance, the Excel user were to paste in an array of values into the range A2:D5, which clearly includes cell C3, the Worksheet_Change macro would have Target.Address as "$A$2". You need to check whether the the cell of particular interest lies within the Range. And possibly also take into account that the range might contain multiple areas.