Event Driven Programming

Event-procedures are Visual Basic procedures that respond to events and are automatically
generated by the Visual Basic.
Visual Basic is based upon an event-driven paradigm, in which each feature included within the
program is activated only when the user responds to a corresponding object (i.e., an icon, a
checkbox, an option button, a menu selection, etc.) within the user interface.
The programmer adds code to respond to specific events, and only events that are relevant to a
program need be coded.
The group of Basic commands that brings about this response is called an event-procedure.

Advantages of Visual Programming
Visual Programming enables
(i) Visual development of graphical user interface which are easy to use and easy to learn
(ii) A programmer need not write code to display the required component.
For example the visual programming environment displays a list of available components.
The programmer picks up the required component from this list to display it.
(iii) The components can be moved resized and even deleted if so required.
(iv) There is no restriction on the number of controls that can be placed on the form.
(v) The programmer can create the user interface visually he can align, move or size the
component as required without having to resort to writing code.
(vi) The interface component provided by the visual programming environment have code
some built into them.
For example a button knows when it has been clicked upon. In the case of conventional
programming tools the programmer has to write code to determine the component that
has been clicked and then execute the appropriate code.

Disadvantages of Visual Programming

(i) AS the name implies the entire process of developing an application using a visual
development environment is visual. Thus the development environment in itself is
highly graphical in nature and therefore requires more memory.
(ii) Visual development environment require computer of a higher configuration in
comparison to the conventional programming tools.
(iii) Lager capacity hard disk
(iv) More RAM
(v) Faster Processor
(vi) Primarily visual development environment can be used with GUI operating systems
such as Windows