Code Organization & OOP›Core· 45 min read

Object-Oriented PHP

Model real things with classes and objects — the foundation Laravel is built on.

What you will learn

Define classes with properties and methods
Create objects
Use $this and the constructor

Classes and objects

A class is a blueprint; an object is an instance built from it. Think of the class as a cookie cutter and each object as a cookie. Properties are its data (like name); methods are its functions (like greet()). $this refers to the current object — "me, this particular cookie".

A class, a constructor, and an object

<?php
  class User {
    public $name;
    public $email;

    public function __construct($name, $email) {
      $this->name = $name;       // -> accesses properties
      $this->email = $email;
    }

    public function greet() {
      return "Hi, I am " . $this->name;
    }
  }

  $asha = new User("Asha", "asha@x.com");
  echo $asha->greet();           // Hi, I am Asha
  echo $asha->email;             // asha@x.com
?>

Walking through it: the class User block is just the blueprint — nothing happens until new User("Asha", "asha@x.com") builds an actual object. Creating it runs the __construct method, which copies the two values into $this->name and $this->email — that object’s own data. Then $asha->greet() calls the object’s method (which reads its own $this->name), and $asha->email reads its stored property directly.

Note: Output (in the browser): Hi, I am Ashaasha@x.com The object $asha carries its own data and behaviour together. Build a second object — $ravi = new User("Ravi", "ravi@x.com") — and $ravi->greet() would say "Hi, I am Ravi", because $this always means *that* object.

class User { } — the blueprint.
__construct — runs when you create the object (new User(...)).
$this->name — the object’s own property.
-> — the arrow to access properties and methods.

Note: This is the heart of modern PHP. Laravel models, controllers and almost everything are classes — master OOP here and Laravel will feel natural.

Q. Inside a class method, what does $this refer to?

Answer: $this refers to the specific object the method is being called on, letting you access its properties and methods.

✍️ Practice

Create a Product class with name and price and a method that returns a label.
Create two objects from it.

🏠 Homework

Build a BankAccount class with a balance, deposit() and withdraw() methods.