Teach Yourself Borland C++ in 14 Days - portal

C++ Class Frameworks and the Visual Component Model
The primary trade-off is that Windows programs written in C++ tend to be larger than their
straight C counterparts. For example, let’s say you had a simple Windows program written
in C that was 75KB in size. The equivalent program written with one of the framework
libraries might end up being 200KB in size. That’s a significant difference, yet this example
demonstrates the worst-case scenario. The difference in final program size between a C
application and a C++ application written with a framework is going to be most noticeable
in very small programs. As your programs increase in size and become more sophisticated,
the difference in size is much less noticeable.
One of the differences is simply the difference between C and C++. C++ carries additional
overhead for features such as exception handling, runtime type information (RTTI), and
other C++ goodies. In my opinion, the difference in code size is an acceptable trade-off for
the features that C++ provides. Now, before you label me as a code-bloat proponent, let me
say that I am as conscientious as the next guy when it comes to code bloat. I believe that we
should all write the tightest code we can, given the tools we use. I am also a realist, and I
understand that time-to-market is a driving force in the software industry today. I am willing
to trade some code size for the power that C++ and an application framework give me.
Frameworks Teach Object-Oriented Programming
and Design
NOTE
If you end up getting serious about this crazy game we call Windows programming, you will
eventually end up peeking into the source code of your favorite framework. Sooner or later
you’ll want to know how the big boys do things. The OWL or VCL source code is a great
place to go for that kind of information.
The MFC source code is probably not the best place to go to see good
object-oriented design in action. MFC lacks the elegance, abstraction,
and overall design that makes a top-notch framework. In addition, it
tends to break OOP rules from time to time. MFC may well be the
most popular framework, but that doesn’t mean it is the best framework
from an OOP standpoint.
Some weekend when the leaves are all raked, the house trim has been painted, the laundry
is all done, the kids are shipped off for a weekend at grandma’s, and you think you have a
pretty good handle on C++, you should spend some time browsing your favorite framework’s
source code. It can be intimidating at first, but after a while you start to see what the designers
were up to. Don’t strain yourself. Attempt to understand the things that bump up against
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