Design patterns are wonderful tools software masters bring to us, which are based upon the object oriented programming. As one of the mostly used design patterns, the Factory Method pattern is also widely leveraged in designing the numerous .NET Framework classes.

In this article, we first introduced the basic idea of the Factory Method pattern with a simple graphic related example. Then, we started to explore the behind implementation of one of the most important web classes-- WebRequest. By seeking after the detailed code related to class WebRequest we have finally dug out the design routine of class WebRequest and tasted the wonderful utilization of the Factory Method pattern.

One last note: I have omitted all the WebRequest associated code in the source code file, so I highly recommend you to pick up Red Gate's .NET Reflector (originally developed by Lutz Roeder) to find out all the related things.