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C++ Destructors Explained with Example

C++ Destructors

This tutorial will teach you about destructors in C++, along with examples to better understand the topic.

What are Destructors in C++?

In brief, Destructors are used to deallocate memory locations and clean up unwanted resources for a specific class and any members that belong to it. You can call a destructor after a class is no longer needed.

Program to demonstrate destructors in C++

First, let’s create a simple program with destructors defined:

#include <iostream>

using namespace std;

class DestructorsDemo {
  int a;
  public:

    DestructorsDemo() {
      a = 0;

      cout << "Constructor Called";
    }~DestructorsDemo() {
      cout << "Destructor Called";
    }

  void GetValue() {
    cout << "Please enter a value of a: ";
    cin >> a;
  }
  void SetValue() {
    cout << endl << "The value of a is " << a;
  }
};

In the program above, we defined a class DestructorsDemo() and a member a. In C++, the Destructor starts with the symbol ~. It will kill the class instant and all members, in this case, the variable a, when it gets called.

Now, let’s call this program from the main class:

int main()
{
    DestructorsDemo destructor;
     
    destructor.GetValue();
     
    cout << endl <<"The value of a in destructor1 is: ";
    destructor.SetValue();
     
    DestructorsDemo destructor2;
     
    destructor2.GetValue();
    cout << endl <<"The value of a in destructor2 is: ";
    destructor2.SetValue();
   
    return 0;
}

Output

Constructor Called
Please enter a value of a: 5

The value of a in destructor1 is: 
The value of a is : 5

Constructor Called
Please enter a value of a: 10

The value of a in destructor2 is: 
The value of a is : 10

Destructor Called

Destructor Called

Happy Coding!

 

Learnmodo Editors

Learnmodo Editors