Quick Answer: What Are The Advantages Of Friend Function In C++?

What is a member function in C++?

Member functions are operators and functions that are declared as members of a class.

Member functions do not include operators and functions declared with the friend specifier.

You can declare a member function as static ; this is called a static member function.

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Which keyword is used to declare the friend function?

Explanation: Friend is used to access private and protected members of a class from outside the same class. 2. Which keyword is used to declare the friend function? Explanation: friend keyword is used to declare a friend function in C++.

Why friend function should be avoided?

1) Friends should be used only for limited purpose. too many functions or external classes are declared as friends of a class with protected or private data, it lessens the value of encapsulation of separate classes in object-oriented programming. 2) Friendship is not mutual.

What is the use of virtual function?

A virtual function is a member function that you expect to be redefined in derived classes. When you refer to a derived class object using a pointer or a reference to the base class, you can call a virtual function for that object and execute the derived class’s version of the function.

What is friend function with example?

In object-oriented programming, a friend function, that is a “friend” of a given class, is a function that is given the same access as methods to private and protected data. … Friend functions allow alternative syntax to use objects, for instance f(x) instead of x.f() , or g(x,y) instead of x.g(y) .

What are the characteristics of friend function?

Characteristics of a Friend function:The function is not in the scope of the class to which it has been declared as a friend.It cannot be called using the object as it is not in the scope of that class.It can be invoked like a normal function without using the object.More items…

Can a friend function be virtual?

A virtual function cannot be global or static because, by definition, a virtual function is a member function of a base class and relies on a specific object to determine which implementation of the function is called. You can declare a virtual function to be a friend of another class.

How do you declare a friend function?

A friend function can access the private and protected data of a class. We declare a friend function using the friend keyword inside the body of the class.

Can not be a friend in C++?

Objects cannot be made friends. friend is a mechanism to control member access and hence, like public , protected and private specifiers, a compile-time issue.

Is it necessary to pass argument in a friend function?

It is possible, to have a friend function with no arguments. It Seldom used. Of course it is possible.

Why do we use friend class in C++?

A friend class is a class that can access the private and protected members of a class in which it is declared as friend. This is needed when we want to allow a particular class to access the private and protected members of a class.

What is friend function and its merits and demerits?

What are the merits and demerits of friend function? A friend function is the friend of the given class which can access all the public, private and protected variables of that class in which it is declared. … It is able to access members without need of inheriting the class.

What is the difference between friend function and friend class?

A friend function is used for accessing the non public member of a class. A class can allow non-member function and other classes to access its own private data by making them friend A Friend class has full access of private data members of another class without being member of that class.

What is a friend class C++?

A friend class in C++ can access the private and protected members of the class in which it is declared as a friend. … Similar to a friend class, a friend function is a function that is given access to the private and protected members of the class in which it is declared as a friend.

Can a friend function be a member of another class?

Friend functions have the following properties: 1) Friend of the class can be member of some other class. 2) Friend of one class can be friend of another class or all the classes in one program, such a friend is known as GLOBAL FRIEND.

Which is more effective while calling the functions?

Which is more effective while calling the functions? Explanation: In the call by reference, it will just passes the reference of the memory addresses of passed values rather than copying the value to new memories which reduces the overall time and memory use. 6.

Why do we need friend function?

The keyword friend is a function specifier and gives a non-member function access to the hidden members of the class, and provides a method of escaping the data hiding restrictions of C++. However, you must have a good reason for escaping these restrictions, as they are both important to reliable programming.

What is use of friend function in C++?

A friend function in C++ is a function that is preceded by the keyword “friend”. When the function is declared as a friend, then it can access the private and protected data members of the class.

What are the advantages of friend function in C++?

– A friend function has the following advantages :Provides additional functionality which is kept outside the class.Provides functions that need data which is not normally used by the class.Allows sharing private class information by a non member function. Next Page »

Are Friend Classes bad?

Instead, try thinking of a friend function as part of the class’s public interface. A friend function in the class declaration doesn’t violate encapsulation any more than a public member function violates encapsulation: both have exactly the same authority with respect to accessing the class’s non-public parts.)