2.1 Creating Your First Application
In this lesson, we will not
delve into the technical aspects of Visual Basic programming yet, what you need
to do is to try out the examples below to see how does a Visual Basic program
looks like:
First of all, you have to launch
Microsoft Visual Basic 6.In the Visual Basic 6 integrated development
environment , a default form with the name Form1 will be available for you to
work on your new project. Now, double click on Form1, the source code window
for Form1 as shown in figure 2.1 will appear. The top of the source code window
consists of a list of objects and their associated events or procedures. In
figure 2.1, the object displayed is Form and the associated procedure is Load.
When you click on the object box, the drop-down
list will display a list of objects you have inserted into your form as shown
in figure 2.2. Here, you can see a form with the name Form1, a command button
with the name Command1, a Label with the name Label1 and a Picture Box with the
name Picture1. Similarly, when you click on the procedure box, a list of
procedures associated with the object will be displayed as shown in figure 2.3.
Some of the procedures associated with the object Form1 are Activate, Click,
DblClick (which means Double-Click) , DragDrop, keyPress and more. Each object
has its own set of procedures. You can always select an object and write codes
for any of its procedure in order to perform certain tasks.
You do not have to worry about the beginning and the end
statements (i.e. Private Sub
Form_Load.......End Sub.); Just key in the lines in between the above two
statements exactly as are shown here. When you press F5 to run the program, you will be
surprised that nothing shown up .In order to display the output of the program,
you have to add the Form1.show statement like in Example 2.1.1
or you can just use Form_Activate
( ) event procedure as
shown in example 2.1.2. The command Print does not mean printing using a printer
but it means displaying the output on the computer screen. Now, press F5 or
click on the run button to run the program and you will get the output as shown
in figure 2.4.
You can also perform arithmetic calculations as shown in
example 2.1.2. VB uses * to denote the multiplication operator
and / to denote the division operator. The
output is shown in figure 2.3, where the results are arranged vertically.
Figure 2.2: List of Objects
Figure 2.3:
List of Procedures
Example 2.1.1
Private Sub Form_Load ( )
Form1.show
Print “Welcome to Visual Basic
tutorial”
End Sub



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