《illustrate c# 2008》：
All Classes Are Derived from Class object
所有的类来自于类object
All classes, except special class object, are derived classes, even if they don’t have a class-base specification. Class object is the only one that is not derived, since it is the base of the inheritance hierarchy.
所有的类，除了类object，都是派生类，即使后面没有 "：SomeClass”之类的"class-base specification".类object，是唯一一个类，这个唯一体现在他不是被派生的，他就是他，因为他是所有继承层次结构的基础。
Classes without a class-base specification are implicitly derived directly from class object.Leaving off the class-base specification is just shorthand for specifying that object is the base class. The two forms are semantically equivalent. Figure 7-2 shows both forms of declaration for the same class.
一个类后面没有 "：SomeClass”之类的"class-base specification"，这个类也是继承类，为什么，因为他implicitly继承于类object。离开了"class-base specification"也就是没有"class-base specification"的类，仅仅是以object类为基类的"shorthand"（简写），下面就来说明这个问题，图7-2显示了2个等价的类声明：
