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2.1 Creating Your First Application
In this section, we will not go into
the technical aspects of Visual Basic programming yet, what you need to do is just try out the examples below
to see how does in VB program look like:
Example 2.1.1 is a simple
program. First of all, you have to launch Microsoft Visual Basic 6. Normally, a
default form with the name Form1 will be available for you to start 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.
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Figure 2.1 Source Code Window
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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.
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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 surprise 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.
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