Differentiate between function overloading and function overriding in C++?
- 3Strange, I am not able to find a duplicate of this question !iammilind– iammilind2012-08-11 05:08:54 +00:00Commented Aug 11, 2012 at 5:08
- 15Is this a question? Or a command?user207421– user2074212014-03-22 08:52:10 +00:00Commented Mar 22, 2014 at 8:52
- 2Kind of sounds like an interview question to me.ahogen– ahogen2019-05-01 03:53:51 +00:00Commented May 1, 2019 at 3:53
11 Answers
Overloading a method (or function) in C++ is the ability for functions of the same name to be defined as long as these methods have different signatures (different set of parameters). Method overriding is the ability of the inherited class rewriting the virtual method of the base class.
a) In overloading, there is a relationship between methods available in the same class whereas in overriding, there a is relationship between a superclass method and subclass method.
(b) Overloading does not block inheritance from the superclass whereas overriding blocks inheritance from the superclass.
(c) In overloading, separate methods share the same name whereas in overriding, subclass method replaces the superclass.
(d) Overloading must have different method signatures whereas overriding must have same signature.
1 Comment
Function overloading is done when you want to have the same function with different parameters
void Print(string s);//Print string void Print(int i);//Print integer Function overriding is done to give a different meaning to the function in the base class
class Stream//A stream of bytes { public virtual void Read();//read bytes } class FileStream:Stream//derived class { public override void Read();//read bytes from a file } class NetworkStream:Stream//derived class { public override void Read();//read bytes from a network } 1 Comment
You are putting in place an overloading when you change the original types for the arguments in the signature of a method.
You are putting in place an overriding when you change the original Implementation of a method in a derived class.
1 Comment
Overriding means, giving a different definition of an existing function with same parameters, and overloading means adding a different definition of an existing function with different parameters.
Example:
#include <iostream> class base{ public: //this needs to be virtual to be overridden in derived class virtual void show(){std::cout<<"I am base";} //this is overloaded function of the previous one void show(int x){std::cout<<"\nI am overloaded";} }; class derived:public base{ public: //the base version of this function is being overridden void show(){std::cout<<"I am derived (overridden)";} }; int main(){ base* b; derived d; b=&d; b->show(); //this will call the derived overriden version b->show(6); // this will call the base overloaded function } Output:
I am derived (overridden) I am overloaded Comments
1.Function Overloading is when multiple function with same name exist in a class. Function Overriding is when function have same prototype in base class as well as derived class.
2.Function Overloading can occur without inheritance. Function Overriding occurs when one class is inherited from another class.
3.Overloaded functions must differ in either number of parameters or type of parameters should be different. In Overridden function parameters must be same.
For more detail you can visit below link where you get more information about function overloading and overriding in c++ https://googleweblight.com/i?u=https://www.geeksforgeeks.org/function-overloading-vs-function-overriding-in-cpp/&hl=en-IN