This is a question about scope.
If you only want the variables to last the lifetime of the function, use Dim
(short for Dimension) inside the function or sub to declare the variables:
Function AddSomeNumbers() As Interger
Dim intA As Integer
Dim intB As Integer
intA = 2
intB = 3
AddSomeNumbers = intA + intB
End Function
'intA and intB are no longer available since the function ended
A global variable (as SLaks pointed out) is declared outside of the function using the Public
keyword. This variable will be available during the life of your running application. In the case of Excel, this means the variables will be available as long as that particular Excel workbook is open.
Public intA As Integer
Private intB As Integer
Function AddSomeNumbers() As Integer
intA = 2
intB = 3
AddSomeNumbers = intA + intB
End Function
'intA and intB are still both available. However, because intA is public, '
'it can also be referenced from code in other modules. Because intB is private,'
'it will be hidden from other modules.
You can also have variables that are only accessible within a particular module (or class) by declaring them with the Private
keyword.
If you're building a big application and feel a need to use global variables, I would recommend creating a separate module just for your global variables. This should help you keep track of them in one place.