摘要： A pure virtual function is a function declared in a base class that has no definition relative to the base. As a result, any derived class must define its own version—it cannot simply use the version ... 阅读全文

摘要： The foundation upon which C++ builds its support for polymorphism consists of inheritance and base class pointers. The specific feature that actually implements polymorphism is the virtual function. T... 阅读全文