查看单元格输出而不是公式的宏

Question

I've used the code from Microsoft's web page so that every time a cell in my range changes, a message box automatically tells me this has happened. The page is: https://support.microsoft.com/en-us/kb/213612

The code I've copied and pasted is (I've very slightly edited it - the edits are in the code below):

Private Sub Worksheet_Change(ByVal Target As Range)
Dim KeyCells As Range

' The variable KeyCells contains the cells that will
' cause an alert when they are changed.
Set KeyCells = Range("B1:B10")

If Not Application.Intersect(KeyCells, Range(Target.Address)) _
       Is Nothing Then

    ' Display a message when one of the designated cells has been 
    ' changed.
    ' Place your code here.
    MsgBox "Cell " & Target.Address & " has changed."

End If
End Sub

However this code isn't doing exactly what I'd like to do. Inside B10 I have the formula:

=IF(D10="709A", IF(AND(D10="709A"), "Yes", "No"), "")

The formula itself isn't important, it's what the formula does. The formula outputs "Yes" in B10 if D10 is input with "709A". Therefore, according to my knowledge, I should automatically get a message box from my macro if I input "709A" into D10, because it changes the value of B10. But I don't. I only get a message box if the formula itself changes, even if the output (value/what's visible in the cell - is there a technical label for this?) doesn't change. How can I create a macro that automatically tells me when the output of a cell changes? Ie: that tells me that the output has changed from "" to "Yes" when D10 is input with "709A"?

Answer 1

A workaround that I can think of is to have an array of variables in the Worksheet_Change event that would store the .value or .value2 property of each of your key cells, and compare it to the changed cell, and trigger your message box that way. The problem is that code is pretty kludgey and can get bulky the more key cells you start watching.

Answer 2

A similar workaround to Roman B's suggestion, but using a global array. This stores the values in B1:B10 when you activate the sheet, then checks and updates every time a change is made in the sheet. This may not be an ideal solution but seems like it may do the job to just check 10 cells.

Option Explicit
Option Base 1

Dim globalArray(10)

Sub Worksheet_Activate()

Dim i As Long

For i = 1 To 10
    globalArray(i) = Cells(i, 2)
Next i

End Sub

Private Sub Worksheet_Change(ByVal Target As Range)

Dim i As Long

For i = 1 To 10
    If globalArray(i) <> Cells(i, 2) Then
        ' Do stuff here
        '
        globalArray(i) = Cells(i, 2)
    End If
Next i

End Sub

Answer 3

It is possible to access the Formula , Text , Value and Value2 properties of a cell. You will need to specify the Value or Value2 of your cell, or Text if you are after formatted text.

MSDN page has more information on these range members. This page addresses difference between properties.