Well, the defines question here is what module level.
we have the standard code modules (that you see on the modules tab),and then
we have for each form a code module is also available.
So, if you declare as you have:
Dim db As Database
Dim rs As Recordset
The above two variables would be available to all code in THAT MODULE ONLY.
So, if it was a forms code module, then all code, events, and anything you
do in that form, those variables would be available to all code in that
forms module. However, other forms, and those other code modules would NOT
be able to see those variables. And, course keep in mind when the form
closes, then those values a re gone, and can't be used by any other
routines.
Now, if we moved the above two vars to a standard code module, then the two
vars would be available to ALL of the routines in THAT ONE code module.
If you wanted variables to be availing everywhere, then you declare them as
public
public db As Database
public rs As Recordset
If you move the above declares back to the forms module, and use the
"public" keyword, then actually all programs and all code CAN access those
variables, but you must tell the code what form the variables are in (if the
code is OUTSIDE of the forms module code).
eg:
inside our forms code module:
msgbox "last name is = " & rst!Lastname
code outside the forms code module:
msgbox "last name is = " & forms!frmCustomers.form.rst!LastName
and, of course if the form is closed..then you can't use those vars.
If you moved the two variables back to the standard code module (as public),
then you have true defined global variables.
eg:
inside our forms code module:
msgbox "last name is = " & rst!Lastname
code outside the forms code module:
msgbox "last name is = " & rst!LastName
So, if you define public in a standard code module, the vars can be used
anywhere, and anytime.
Do keep in mind that any un-handled code error will re-set both local, and
global var values. this is one good reason as to why you want to distribute
a mde to your end users (a un-handled error does NOT re-set the value of all
variables).
Note that if you declare the variables in a sub, or function, then when you
exit the sub, then the variables are gone. And, at a forms module, when you
exit the form..then those variables are gone. The ones in a module don't go
away. This common concept is referred to as "scope".
The most easy way to think of this is that each higher level you go, you are
throwing a card on top of a deck. And, as you exit out of routines and
modules...you pulling the cards back. this is important, since you can
actually declare the same variables a code module, forms modules, and then
each sub inside of the module. Each higher level you go takes precedence
over the previous.
