Accumulatar Cell

[Shatin]

On a worksheet:

In cell A1 is a number.
In cell B1 is another number.
In cell C1 is the formula: = sum(A1+B1)

The values in A1 and B1 are downloaded from the web and change constantly.

What I want to do is to use cell D1 to accumulate the values of C1.

For example
A1 = 100, B1 = 200, C1 = 300, D1 = 300
A1 = 200, B1 = 300, C1 = 500, D1 = 300 + 500 = 800, etc.

Presumably, I can use to a worksheet change event to capture the changes in
C1 to put them in D1. The problem is C1 depends on A1 and B1. Thus, when
there is a new value in A1, C1 changes. Then when there's a new value in B1,
C1 changes again. So the value in A1 will be double counted. How can I make
sure that the worksheet change event only fires when both A1 and B1 have new
values?

TIA.

 

[Bob Phillips]

Private Sub Worksheet_Change(ByVal Target As Range)
Const WS_RANGE As String = "A1:B1"

On Error GoTo ws_exit:
Application.EnableEvents = False
If Not Intersect(Target, Me.Range(WS_RANGE)) Is Nothing Then
Range("D1").Value = Range("D1").Value + Target.Value
End If

ws_exit:
Application.EnableEvents = True
End Sub

'This is worksheet event code, which means that it needs to be
'placed in the appropriate worksheet code module, not a standard
'code module. To do this, right-click on the sheet tab, select
'the View Code option from the menu, and paste the code in.


--

HTH

RP
(remove nothere from the email address if mailing direct)

 

[Mike]

On a worksheet:

Hello Shatin,
the <Change Event> occurs only when cells on the worksheet are changed
by the user
The <Worksheet_Calculate> event occurs after the worksheet is recalculated.
So if you disable automatic calculation, you can use the
<Worksheet_Calculate> event to update cell 'D1'
But you have to disable automatic calculation , otherwise values are
double counted.

Private Sub Worksheet_Calculate()
Range("D1").Value = Range("D1").Value + Range("C1").Value
End Sub


Mike, from Luxembourg

 

[robinsonie]

You could keep 2 public variables, say A1Ref and B1Ref, and on the
worksheet change event have something like this

if range("A1").value <> A1Ref AND range("B1").value <> B1Ref then
range("D1").value = range("A1").value + range("B1").value
A1Ref = range("A1").value
B1Ref = Range("B1").value
End If

Although the problem with this is if A1 changes twice before B1 changes
or vice versa, would this happen?

 

[Jim May]

Thanks for your input Mike.
Isn't another piece to this the fact that the OP needs to also know that if
he changes Calculation mode "from Automatic - via Tools, Options to
Manual" - this is going to affect ALL other Excel workbooks!! so, in this
same specific file it would probably be best to create an Workbook_Open
event making the change Calc from Automatic to Manual and also a
Workbook_Close event to reverse setting of Calc from Manual to Automatic.
PLUS - he'll need to remember (all the time the file is open that any other
Workbooks he works with will **AT THE TIME** also have Calc set to MANUAL,,,

Right?
Please clarify anything I've stirred up here, Tks...
Jim

 

[Tom Ogilvy]

I think Bob gave you the best answer, but if you want to specifically wait
until both A1 and B1 have changed, I think this will work as well.

Private Sub Worksheet_Change(ByVal Target As Range)
Static bA1Change as Boolean
Static bB1Change as Boolean

If Target.count >1 then exit sub
If Target.Address <> "$A$1" and _
Target.Address <> "$B$1" Then exit sub

If Target.Address = "$A$1" then _
bA1Change = True
If Target.Address = $B$1" then _
bB1Change = True
if bA1Change and bB1Change then
On Error GoTo ErrHandler
Application.EnableEvents = False
Range("D1").Value = Range("D1").Value + Range("C1").Value
bA1Change = False : bB1Change = False
End If

ErrHandler:
Application.EnableEvents = True
End Sub

This assumes that whatever updates A1 and B1 fires a change event.

 

[Shatin]

Thanks to all for you help!