Importing with use keyword in PHP - Mini Project: Build & Apply

Importing with use keyword

📖 Scenario: Imagine you are organizing a small library of books. Each book belongs to a category, and you want to use short names to refer to these categories in your code.

🎯 Goal: You will create two classes in different namespaces and then use the use keyword to import these classes with shorter names. Finally, you will create objects from these classes and print their category names.

📋 What You'll Learn

Create two classes in separate namespaces: Library\Fiction\Book and Library\NonFiction\Book

Each class should have a public method getCategory() that returns the string 'Fiction' or 'Non-Fiction' respectively

Use the use keyword to import these classes with aliases FictionBook and NonFictionBook

Create objects of FictionBook and NonFictionBook and print their categories

💡 Why This Matters

🌍 Real World

Namespaces and the <code>use</code> keyword help organize large PHP projects by grouping related code and avoiding name conflicts.

💼 Career

Understanding namespaces and imports is essential for working on professional PHP applications, frameworks, and libraries.

1

Create two classes in namespaces

Create two classes: Book inside namespace Library\Fiction and another Book inside namespace Library\NonFiction. Each class should have a public method getCategory() that returns 'Fiction' for the first and 'Non-Fiction' for the second.

PHP

<?php

// Define class Book in namespace Library\Fiction
// Define class Book in namespace Library\NonFiction
# Your code here

Need a hint?

Use the namespace keyword to define namespaces. Define the Book class inside each namespace with the getCategory() method returning the correct string.

2

Import classes with use keyword and alias

After the namespace declarations, use the use keyword to import Library\Fiction\Book as FictionBook and Library\NonFiction\Book as NonFictionBook.

PHP

<?php

namespace Library\Fiction {
    class Book {
        public function getCategory() {
            return 'Fiction';
        }
    }
}

namespace Library\NonFiction {
    class Book {
        public function getCategory() {
            return 'Non-Fiction';
        }
    }
}

use Library\Fiction\Book as FictionBook;
use Library\NonFiction\Book as NonFictionBook;
# Your code here

Need a hint?

Use the use keyword followed by the full namespace and class name, then as and the alias name.

3

Create objects using the aliases

Create two variables: $fictionBook as a new FictionBook object and $nonFictionBook as a new NonFictionBook object.

PHP

<?php

namespace Library\Fiction {
    class Book {
        public function getCategory() {
            return 'Fiction';
        }
    }
}

namespace Library\NonFiction {
    class Book {
        public function getCategory() {
            return 'Non-Fiction';
        }
    }
}

use Library\Fiction\Book as FictionBook;
use Library\NonFiction\Book as NonFictionBook;

$fictionBook = new FictionBook();
$nonFictionBook = new NonFictionBook();
# Your code here

Need a hint?

Create new objects by calling new with the alias names.

4

Print the categories of the books

Print the category of $fictionBook by calling getCategory() and then print the category of $nonFictionBook by calling getCategory(). Each category should be printed on its own line.

PHP

getCategory() . "\n");
print($nonFictionBook->getCategory() . "\n");
# Your code here

Need a hint?

Use print() to display the category strings returned by getCategory(). Add a newline character \n after each.