Destructor method in PHP - Mini Project: Build & Apply

Destructor method

📖 Scenario: Imagine you are managing a simple library system. Each book is represented by an object. When a book object is no longer needed, it should announce that it is being removed from the system.

🎯 Goal: You will create a PHP class called Book with a destructor method that prints a message when a book object is destroyed.

📋 What You'll Learn

Create a class named Book

Add a constructor method that sets the book's title

Add a destructor method that prints a message when the object is destroyed

Create an instance of the Book class

Destroy the object to see the destructor message

💡 Why This Matters

🌍 Real World

Destructors help clean up resources or show messages when objects are no longer needed, like closing files or freeing memory.

💼 Career

Understanding destructors is important for managing resources efficiently in PHP applications, especially in web development and backend programming.

1

Create the Book class with a title property

Create a class called Book with a public property title. Add a constructor method __construct that takes one parameter $title and assigns it to the title property.

PHP

<?php

// Create class Book with public property title and constructor method __construct
// Your code here

Need a hint?

Use class Book {} to create the class. Inside, declare public string $title;. Then add public function __construct(string $title) { $this->title = $title; }.

2

Add a destructor method to the Book class

Inside the Book class, add a destructor method named __destruct that prints the message "Destroying book: " followed by the book's title and a newline.

PHP

title = $title;
    }

    // Add destructor method __destruct here
    // Your code here
}

Need a hint?

Define public function __destruct() { echo "Destroying book: " . $this->title . "\n"; } inside the class.

3

Create a Book object with the title "PHP Basics"

Create a variable named $myBook and assign it a new Book object with the title "PHP Basics".

PHP

title = $title;
    }

    public function __destruct() {
        echo "Destroying book: " . $this->title . "\n";
    }
}

// Create a Book object with title "PHP Basics"
// Your code here

Need a hint?

Write $myBook = new Book("PHP Basics"); to create the object.

4

Destroy the $myBook object to trigger the destructor

Use the unset function on the variable $myBook to destroy the object and trigger the destructor message.

PHP

title = $title;
    }

    public function __destruct() {
        echo "Destroying book: " . $this->title . "\n";
    }
}

$myBook = new Book("PHP Basics");

// Destroy the $myBook object
// Your code here

Need a hint?

Use unset($myBook); to remove the object and see the destructor message.