23种设计模式中的观察者模式，用c++实现了解耦实践一、解耦实践二、以及委托，委托代码的实现使用的vs2008 sp1以上版本才支持的std::tr1-Observer mode, 23 kinds of design patterns implemented in c++ decoupling practice, decoupling practice and commissioned, commissioned vs2008 sp1 version of the code' s imp

实现了23种设计模式中的工厂模式，提供给初学者学习义工参考-23 kinds of design patterns to achieve the factory model, to provide a reference for beginners to learn the volunteers