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Arrow Operator as Class Member Access Operator in C++

Learn: How to use Arrow Operator instead of Class Member Access Operator in C++ programming language, how to access members of a class through object pointer in C++?

Previously, we have discussed about Class Member Access Operator in C++ , which is used to access public members of a class.

To access public members of a class, we use object_name.member_name.

Accessing Class Members with Pointer to an Object

If you have a pointer to an object and want to access the class members, you can access them by using combination of two operators Asterisk (*) and Dot (.) operator.

Syntax

(*object_pointer_name).member_name;

Class declaration

Consider the given class declaration

class sample {
 private:
  int a;

 public:
  int b;
  void init(int a) { this->a = a; }
  void display() { cout << "a: " << a << endl; }
};

The main() function

Consider the main(), here we are accessing the member function by using combination of * and . Operators:

int main() {
  // pointer to an object declaration
  sample *sam = new sample();

  // value assignment to a and back
  (*sam).init(100);
  (*sam).b = 200;

  // printing the values
  (*sam).display();
  cout << "b: " << (*sam).b << endl;

  return 0;
}

Arrow Operator (->) instead Asterisk (*) and Dot (.) Operator

We can use Arrow Operator (->) to access class members instead of using combination of two operators Asterisk (*) and Dot (.) operator, Arrow operator in also known as “Class Member Access Operator” in C++ programming language.

Syntax

object_pointer_name -> member_name;

The main() function

Consider the main(), here we are accessing the members using Arrow Operator

int main() {
  // pointer to an object declaration
  sample *sam = new sample();

  // value assignment to a and back
  sam->init(100);
  sam->b = 200;

  // printing the values
  sam->display();
  cout << "b: " << sam->b << endl;

  return 0;
}

Example of Arrow Operator as Class Member Access Operator

Consider the below example, here we are demonstrating the use and working of arrow operator as class member access operator in C++:

#include <iostream>
using namespace std;

class sample {
 private:
  int a;

 public:
  int b;
  void init(int a) { this->a = a; }
  void display() { cout << "a: " << a << endl; }
};

int main() {
  // pointer to an object declaration
  sample *sam = new sample();

  cout << "Using * and . Operators\n";
  // value assignment to a and back
  (*sam).init(100);
  (*sam).b = 200;

  // printing the values
  (*sam).display();
  cout << "b: " << (*sam).b << endl;

  cout << "Using Arrow Operator (->)\n";
  // value assignment to a and back
  sam->init(100);
  sam->b = 200;

  // printing the values
  sam->display();
  cout << "b: " << sam->b << endl;

  return 0;
}

Output

Using * and . Operators 
a: 100
b: 200
Using Arrow Operator (->) 
a: 100
b: 200