Calculations

Using visual basic you can perform any type of calculation that is needed. The four types that will be covered here are:

• Addition +
• Subtration -
• Multiplication *
• Division /

To see the example code that goes along with lesson go https://github.com/majorsilence/VB-Notes/tree/master/VbBook1/Calculations/Application.vb

This example is going to use the variable a which is an Integer. For an example using decimals see the code example linked above.

Dim a As Integer = 2
System.Console.WriteLine("A is: " & a.ToString)

The first example will cover addition. You can add a number like so

1 + 1

In visual basic we will add 2 to the integer a we declared above. This will make the variable a equal 4.

a = (a + 2) ' Addition
System.Console.WriteLine("A + 2 is: " & a.ToString)

To subtract a number from a, in this case 1, we will end up with 3.

a = (a - 1) ' Subtraction
System.Console.WriteLine("A - 1 is: " & a.ToString)

Next if we want to multiple we can do it like this.

a = (a * 3) ' Multiplication
System.Console.WriteLine("A * 3 is: " & a.ToString)

Now a is equal to 9.

The final action that we will perform is division. We will divide 9 by 2 and it will equal 4. You need to remember that we are doing integer calculations so any decimal places will be rounded up or down.

a = CInt(a / 2) ' Division
System.Console.WriteLine("A / 2 is: " & a.ToString)

You should have also noted the use of the function CInt. When compiling vb in strict mode when the result will result in a decimal we cannot assign to an integer unless we cast the value. CInt is a visual basic function to cast values. For more details on casting or converting values see the Convert class in the .NET library.

If you want precise values you should use Decimals instead of Integers.