Parts of a Program
A program is made up of the basic parts shown in Figure 2-1.
- Project
Is the workbook where the program is stored. Each workbook has one Visual Basic project.
- Classes and modules
Store the code associated with the workbook and the sheets the workbook contains. Classes and modules help organize the procedures in your program.
- Procedures
Perform the program’s work. You can’t do anything in Visual Basic without creating at least one procedure.
Figure 2-1. The main parts of a program
- Variables
Store values used by your program.
- Conditional statements
Make decisions within procedures.
- Loops
Repeat actions. Together, conditional statements and loops form the logic that your procedure uses to accomplish its task.
- Expressions
Evaluate a combination of items to return a single result. Expressions are the smallest unit of work in a program and they usually involve operators such as
+,-,*, or&(combine strings).
The following sections describe these parts in detail. If you are new to programming, I recommend that you follow along with the samples carefully. I take a top-down approach and I’ve tried to be clear about how, when, and why you use each part.
If you’re an experienced programmer, the top-down organization of this chapter should work well for you as a reference. If you think you know this already, I recommend that you read the sections "Classes and Modules,” ...
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