Introduction
What are classes and controls? A control is something you put on a form, with
methods (procedures and functions), properties, constants, and events. A class
is basically the same, except you can't place it on a form, or set its properties
at design-time.
Why should we use them? If you have a large project, have lots of people working
on a project, or have a large number of little projects, you will find that
there are portions of code that you are using over and over again. You will
also find that you don't want co-programmers changing core parts of your project,
which mean that you have to change hundreds of other lines of code too! Using
classes and controls, you can break a project up into small, manageable portions.
Controls and classes can also be compiled into DLL's or OCX controls, so people
can use your code without seeing what is actually behind it, just like when
you use the standard Microsoft controls. This is what VB web does when creating
its free (and in this case, open source) controls and DLLs.