executing different formulae based on null values

Hi All,

I have a dialog box that is used to collect four values and perform calcs
based on the values. My objective is to calculate the value of the empty
edit box, given the other parameters. For example, A+B+C=D but if the user
lets B blank, B is calculated. I know how to rearrange the formulae but how
do I test which formula to apply and then actually apply it?

Thanks,
GLC

 

If you are saying 1 of the boxes is to be empty and it can be any of them,
make sure you have a button to do the calc. The first thing the button
should do is check for only 1 empty value. A simple way would be to create
a Collection object and have the Exit event [vba] for the textbox add its
value to the collection. Then before doing the calc, check to make sure
there are 3 items in the collection. From there, use an If..ElseIIf
structure to determine which formula to use:

If myCollection.Count = 3 Then
If TextboxA.Text = vbnullstring Then
A = B+C+D
ElseIf TextboxB.Text vbnullstring Then
B = A+C+D
ElseIf TextboxC.Text = vbnullstring Then
C = A+B+D
Else
'Must be D
D = A+B+C
End If
End If
'make sure to reset your collection for next pass
Set myCollection = New Collection

-- Mike
___________________________
Mike Tuersley
CADalyst's CAD Clinic
Rand IMAGINiT Technologies
___________________________
the trick is to realize that there is no spoon...