15.1--Object-oriented

Data abstraction, inheritance, dynamic binding

(1) in C + +, dynamic binding occurs when a virtual function is called through a pointer or reference to a base class, either to a base class object or to a derived class object

This fact is the key to dynamic binding. A virtual function called with a reference or pointer determines at run time that the called function is the object referred to by the reference or pointer

The actual type.

(2) Any non-static member function can be a virtual function, virtual function virtual Word can only appear in the class body

Access control:

(1) Private member: The private member of the base class can only be accessed by the member functions and friends of the base class.

(2) A derived class can access only public members of the base class and cannot access private (access rights are the same as other programs)

(3) Protected members: derived classes can be accessed, but other ordinary users are still inaccessible.

15.1--Object-oriented