C + + fundamentals (eight)

One, the type of the decisive

By accessing a member of a class to a pointer or reference, the compiler simply determines whether the member can be accessed based on the pointer or the type referenced, regardless of the actual target object of the pointer or reference.

Second, virtual function and polymorphism

If a member function in a base class is declared as a virtual function (preceded by its return type with the virtual keyword), the same function in its subclass is also a virtual function (whether or not it has the virtual keyword), and it forms an overlay with the base class version.

This virtual function is called by a base-class pointer to a subclass object or a reference to a subclass object, which is actually

C + + fundamentals (eight)