What is the difference between overload and override?

Method overloading and rewriting are ways to implement polymorphism , The difference is that the former implements compile time polymorphism , The latter implements runtime polymorphism .

heavy load ： There are multiple methods with the same name in a class , But there are different parameter lists （ Different parameter types 、 The number of parameters is different or both are different ）.

rewrite ： Occurs between the subclass and the parent , Subclasses override the methods of the parent class , None of the parameters can be changed , Return value types can be different , But it must be a derived class of the return value of the parent class . That is, the shell remains the same , Core rewrite ！ The advantage of overriding is that subclasses can be as needed , Define your own actions .