VISUAL BASIC
What is Visual Basic?
•The "Visual" part refers to the method used to create the graphical user interface (GUI). Rather than writing numerous lines of code to
describe the appearance and location of
interface elements, you simply add pre-built
objects into place on screen
•The "Basic" part refers to the BASIC
(Beginners All-Purpose Symbolic Instruction
Code) language
(Beginners All-Purpose Symbolic Instruction
Code) language
Visual Basic Characteristics
• Rapid Application Development (RAD) tool
• Front-end applications.
•ActiveX technologies allow you to use the functionality provided by other applications, such as Microsoft Word word processor, Microsoft Excel spreadsheet, and other Windows applications.
•Your finished application is a true .exe file
• Front-end applications.
•ActiveX technologies allow you to use the functionality provided by other applications, such as Microsoft Word word processor, Microsoft Excel spreadsheet, and other Windows applications.
•Your finished application is a true .exe file
Event-Driven programming Language?
In an event-driven application, the code doesn't follow a
predetermined path — it executes different code sections in
response to events.
Events can be triggered by the user's actions, by messages
from the system or other applications, or even from the
application itself.
from the system or other applications, or even from the
application itself.
The sequence of these events determines the sequence in
which the code executes, thus the path through the
application's code differs each time the program runs
Your code can also trigger events during execution. For
example, programmatically changing the text in a text box
cause the text box's Change event to occur
which the code executes, thus the path through the
application's code differs each time the program runs
Your code can also trigger events during execution. For
example, programmatically changing the text in a text box
cause the text box's Change event to occur
Interactive Development
The traditional application development process can be broken into three distinct steps:writin g,compiling, and testing code. Unlike traditional languages, Visual Basic uses an interactive approach to development, blurring the distinction between the three steps.
With most languages, if you make a mistake in writing your
code, the error is caught by the compiler when you start to
compile your application. You must then find and fix the error
and begin the compile cycle again, repeating the process for
each error found.
Visual Basic interprets your code as you enter it, catching and highlighting most syntax or spelling errors on the fly
In addition to catching errors on the fly, Visual Basic also
partially compiles the code as it is entered. If the compiler
finds an error, it is highlighted in your code. You can fix the
error and continue compiling without having to start over.
partially compiles the code as it is entered. If the compiler
finds an error, it is highlighted in your code. You can fix the
error and continue compiling without having to start over.
Because of the interactive nature of Visual Basic, you'll find
yourself running your application frequently as you develop
it. This way you can test the effects of your code as you
work rather than waiting to compile later.
to download this course click here
yourself running your application frequently as you develop
it. This way you can test the effects of your code as you
work rather than waiting to compile later.
to download this course click here
No comments:
Post a Comment