Destructor role in C++ - Mini Project: Build & Apply

Destructor role

📖 Scenario: Imagine you have a simple program that manages a book in a library. When the book object is no longer needed, it should clean up by announcing it is being removed.

🎯 Goal: You will create a class Book with a destructor that prints a message when the object is destroyed. This shows how destructors help clean up or notify when an object is removed.

📋 What You'll Learn

Create a class named Book

Add a constructor that sets the book's title

Add a destructor that prints "Destroying book: <title>"

Create a Book object with the title "C++ Basics"

Allow the destructor message to show when the object goes out of scope

💡 Why This Matters

🌍 Real World

Destructors help manage resources like memory or files by cleaning up automatically when objects are no longer needed.

💼 Career

Understanding destructors is important for writing safe and efficient C++ programs, especially in systems programming and software development.

1

Create the Book class with a title

Write a class named Book with a public string variable title. Add a constructor that takes a string parameter bookTitle and sets title to it.

C++

// Your code here

Need a hint?

Use class Book and add a constructor that sets the title variable.

2

Add a destructor to the Book class

Inside the Book class, add a destructor ~Book() that prints "Destroying book: " followed by the title and a newline.

C++

#include 
#include 

class Book {
public:
    std::string title;
    Book(std::string bookTitle) {
        title = bookTitle;
    }
    // Your code here
};

Need a hint?

Destructor has the same name as the class but with a tilde ~ before it.

3

Create a Book object in main

Write a main function that creates a Book object named myBook with the title "C++ Basics".

C++

#include 
#include 

class Book {
public:
    std::string title;
    Book(std::string bookTitle) {
        title = bookTitle;
    }
    ~Book() {
        std::cout << "Destroying book: " << title << std::endl;
    }
};

int main() {
    // Your code here
}

Need a hint?

Create the myBook object inside main() using the constructor.

4

Run the program to see the destructor message

Add a return 0; statement at the end of main(). Run the program and observe the output showing the destructor message.

C++

#include 
#include 

class Book {
public:
    std::string title;
    Book(std::string bookTitle) {
        title = bookTitle;
    }
    ~Book() {
        std::cout << "Destroying book: " << title << std::endl;
    }
};

int main() {
    Book myBook("C++ Basics");
    // Your code here
}

Need a hint?

The destructor message appears when myBook goes out of scope at the end of main().