PHP Call methods of objects in array using array_map?

In PHP, you can call methods of objects in an array using array_map() function. This is useful when you need to extract the same property or call the same method on multiple objects.

Using Anonymous Functions (PHP 5.3+)

The most straightforward approach uses anonymous functions −

<?php
class Product {
    private $name;
    private $price;
    
    public function __construct($name, $price) {
        $this->name = $name;
        $this->price = $price;
    }
    
    public function getName() {
        return $this->name;
    }
    
    public function getPrice() {
        return $this->price;
    }
}

$products = [
    new Product("Laptop", 999.99),
    new Product("Mouse", 25.50),
    new Product("Keyboard", 75.00)
];

$names = array_map(function($obj) { return $obj->getName(); }, $products);
$prices = array_map(function($obj) { return $obj->getPrice(); }, $products);

print_r($names);
print_r($prices);
?>

Array
(
    [0] => Laptop
    [1] => Mouse
    [2] => Keyboard
)
Array
(
    [0] => 999.99
    [1] => 25.5
    [2] => 75
)

Using Named Functions

You can also define a separate function for better readability −

<?php
class User {
    private $email;
    
    public function __construct($email) {
        $this->email = $email;
    }
    
    public function getEmail() {
        return $this->email;
    }
}

function extractEmail($user) {
    return $user->getEmail();
}

$users = [
    new User("john@example.com"),
    new User("jane@example.com"),
    new User("bob@example.com")
];

$emails = array_map('extractEmail', $users);
print_r($emails);
?>

Array
(
    [0] => john@example.com
    [1] => jane@example.com
    [2] => bob@example.com
)

Performance Comparison

Conclusion

Use array_map() with anonymous functions for clean, functional programming style when performance isn't critical. For better performance with large arrays, consider using foreach loops instead.