Visual Basic Arithmetic

Two areas where computer systems excel are arithmetic and logic. Given this fact, it should come as no surprise that a lot of programming tasks also involve arithmetic and logic. The purpose of this chapter is to cover both these topic areas in the context of Visual Basic programming.

Understanding Expressions

Arithmetic calculations and logical evaluations are defined in Visual Basic using expressions. The calculation 1 + 1 is, for example, an expression.

Expressions consist of two key components called operators and operands. The operands define the values or variable on which the arithmetic or logical evaluation are to be made. The operator defines what action is to be performed on the operands. Often, an assignment operator is also used to define what should happen to the result of the expression. This is, perhaps, best explained using an example:

Dim intResult As Integer

intResult = 4 + 5

In the above example, the numbers '4' and '5' are both operands. The '+' is an operator which adds together the two operands. Similarly, the '=' is an operator which assigns the result of the addition to the intResult variable which is an operand.

A logical expression uses operators and operands to make a decision of some sort. For example:

Dim intResult As Integer = 10

If intResult < 20 Then
       MessageBox.Show("Result is less than 10")