C + + overloading, overriding, redefining

1. Overloading:
Overloading is a series of functions in which a class, like a function name, has a different parameter type or number of arguments
It is important to note that it is independent of the return type.

 class   test{ public  :  void      show ();  void  Show (int   a);  void  Show (double   a);  void  Show (int  a,int   b);  void  Show (int  a,double   b);};  

2. Rewrite
Another word we're more familiar with is "overlay."
In the case of inheritance, if the subclass does not redefine the virtual method of the parent class , the child class object is still using the method of the parent class when calling the method;
Otherwise, the child class overrides the virtual method of the parent class, which is called with a redefined method.

classtest{ Public:    Virtual voidShow () {Std::cout<<"test::show ()"<<Std::endl; }};classSubtest: Publictest{ Public:    Virtual voidShow () {Std::cout<<"subtest::show ()"<<Std::endl; }};intMain () {Test*p =Newsubtest; P-Show (); return 0;}

Output Result:
Subtest::show ()

3. Redefining
Another word we're more familiar with is "hiding."
subclasses redefine a non-virtual function in the parent class that has the same name , and then the object calls the non-virtual method, using the method defined by the object itself.

classtest{ Public:        voidShow () {Std::cout<<"test::show ()"<<Std::endl; }};classSubtest: Publictest{ Public:    Virtual voidShow () {Std::cout<<"subtest::show ()"<<Std::endl; }};intMain () {Test*p =Newsubtest; P-Show (); return 0;}

Output Result:
Test::show ()

With respect to rewriting and redefinition, it is easy to understand the principle of a virtual function table,
On virtual function table, refer to C + + virtual function table and virtual destructor function

C + + overloading, overriding, redefining