Friend Function in C++ | Mohd Abuzar

Through this video we are learning about friend function in c++

Function is defined as a friend function  in c++  , then the private and protected data member can be accessed using the function .

By using this keyword compiler knows that this is friend function 

Characteristic of Friend function in c++ 

• The function is not in the scope which is declared as friend function 
• It is not called using the object 
• It can be Invoked like normal function without using the object 
• It can not accessed the member name directly 
• It is accessed by function name dot member operator with the member name
• It can declared in private , protected or public function.      

  C++ friend function Example  

1. #include <iostream>    
2. using namespace std;    
3. class Box    
4. {    
5.     private:    
6.         int length;    
7.     public:    
8.         Box(): length(0) { }    
9.         friend int printLength(Box); //friend function    
10. };    
11. int printLength(Box b)    
12. {    
13.    b.length += 10;    
14.     return b.length;    
15. }    
16. int main()    
17. {    
18.     Box b;    
19.     cout<<"Length of box: "<< printLength(b)<<endl;    
20.     return 0;    
21. }    

Output : 

Length of box: 10

In the above Code you will see that what is friend function and how friend function works.

This article is Contributed by Mohd Abuzar . If you like Code with abuzar  or want to give 

more suggestion or write something you can mail at abuzar.abuzar.mohd325@gmail.com

Please write comment if you find anything incorrect .