Objects

An object is a value that bundles data (called properties) and actions (called methods) in one package. You create objects from a blueprint called a class.

Think of a class as a cookie cutter and objects as the cookies.

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<?php
class Car
{
    public string $brand = "Tata";

    public function honk(): string
    {
        return "Beep!";
    }
}

$car = new Car();

echo $car->brand . "\n";
echo $car->honk();

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Tata
Beep!

• class Car defines the blueprint.
• new Car() creates one object.
• -> reaches inside the object to read a property or call a method.

Checking an object

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<?php
class Car {}
$car = new Car();

var_dump($car instanceof Car);
echo get_debug_type($car);

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bool(true)
Car

The built-in stdClass

PHP has an empty class called stdClass for quick, plain objects. You will often meet it when decoding JSON.

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<?php
$point = new stdClass();
$point->x = 10;
$point->y = 20;

echo $point->x + $point->y;

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Objects are handled by reference

Assigning an object to another variable does not copy it. Both variables point to the same object.

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<?php
$a = new stdClass();
$a->name = "first";

$b = $a;
$b->name = "changed";

echo $a->name;

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changed