Microsoft® Office Access 2003 Inside Out

Variables and Constants

In addition to using Visual Basic code to work with the controls on any open forms or reports (as you can with macros), you can declare and use named variables in Visual Basic code for storing values temporarily, calculating a result, or manipulating any of the objects in your database. To create a value available anywhere in your code, you can define a global variable, as you can find in the modGlobals module in the LawTrack Contacts sample database.

Another way to store data in Visual Basic is with a constant. A constant is a data object with a fixed value that you cannot change while your application is running. You’ve already encountered some of the built-in constants in Microsoft Access—Null, True, and False. Visual ...