Visual Basic Variables

Variables allow us to store and retrieve data. Variables are storage locations and the data is held in the computer’s memory (RAM). In Visual Basic, variables start with the Dim keyword.

Syntax

Dim  <variable name> As <data type>

VB supports a number of data types; the common ones are:

Data Type	Description
Integer	Whole Numbers
Floating Point	Numbers with decimals e.g. 5.2
Boolean	True Or False
Double	Floating Point numbers but more accurate
Char	Single characters

Variables can start with uppercase or lowercase characters.

Create a new VB Console Application and name it Variables. Between the Sub Main() and End Sub, type the following:

 Sub Main()

        Dim myNumber As Integer
        myNumber = 5

        Console.WriteLine(myNumber)
        Console.ReadLine()

    End Sub

Hit F5 or click the green play icon on the toolbar. You should see the result 5.

Code Explained

First we use the Dim keyword to create the variable myNumber
Next we assign the value 5 to myNumber
We then use the Console.WriteLine command to print out myNumber
Finally, we use Console.ReadLine to read that line

String Variables are wrapped in quotation marks; comment out the above code, highlight it all and press CTRL+K+C (to un-comment, CTRL+K+U). Next, type the following:

  Dim name As String

        name = "Asim"

        Console.WriteLine(name)
        Console.ReadLine()

This should print out Asim. This code works the same as above, but this time it was a string data type. You can also add, subtract and perform other mathematical calculations. Under the above code, write the following:

   Dim x As Integer
   Dim y As Integer

        x = 32
        y = 15

        Console.WriteLine(x + y) 'Add x (32) and y(15) ( 32 + 15 = ?)
        Console.ReadLine() ' ReadLine

You should get the value 47. This time we made two integer variables called x and y, assigned them a value, and then added them together.

Summary

Variables start with the Dim keyword
Variables can start with uppercase or lowercase characters