C#源码及可执行程序，里面对C#中的委托和设计模式中的观察者模式进行了比较，注视非常详细，例子是根据李建忠设计模式讲义编写的，很实用。-C# source code and executable programs, which for C# in the commissioning and design of the observer mode model compared to a very detailed attention, for example, LI Jian-zhong desi