in VBA Why does the Selection Object act differently when indexed? - vba

Question

hopefully you can help me with this!
I am writing a code in VBA and I am having issues with the Selection object acting differently than I expect.
When I write a for loop as in
For Each Cell in Selection
MsgBox Cell.Value
Next Cell
It works as expected, but then I try to index it and it acts differently. Especially it is a non-contiguous cell selection.
Like this;
For i = 0 to 5
MsgBox Selection(i).Value
Next i
It gives pretty random values. any insight would be great!
Edit:
Thanks for the input everyone, it seems I need to find another way of doing the following. I have a piece of code that takes a user's selected cells and uses those values for calculations. Right now, I have been trying to make it so they can select non-contiguous cells. Basically, I need to make an array of these values, and my thoughts were to make a for loop as follows
For I = 0 To 5
Array(i) = Selection(i).Value
Next I
I'm not sure if there is another way of doing this. If anyone has some suggestions, I am interested!

Answer 1

As others have stated, you should not use Selection this way. But to answer your question...I did some quick testing based on your example use-case.
It appears that when you loop cell in Selection it goes left to right, then top to bottom by range area. So for example if you have two non-contiguous ranges selected then if will look something like this:
When you index it, it does not seem to make the jump between range areas. instead it will continue iterating left to right top to bottom within the column bounds of the first range area:
So if you slected 2 columns, iterating on the index would just continue down the first column, even if it is outside of the selection.
My test code:
Private Sub testing()
Dim i As Integer
For i = 1 To Selection.Cells.Count
Selection(i).Value = i
Next i
End Sub
Private Sub testing2()
Dim c As Range
For Each c In Selection.Cells
c.Value = c.Column
Next c
End Sub