__get and __set for property access in PHP - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of the __get magic method in PHP?

The __get method is called when reading data from non-existing properties. It allows you to control what happens when you try to access such properties.

beginner

What does the __set magic method do in PHP?

The __set method is called when writing data to non-existing properties. It lets you define how to handle setting values to those properties.

intermediate

How do __get and __set help with property access in PHP classes?

They let you control reading and writing to non-existing properties, making your class flexible and secure by managing property access.

beginner

Show a simple example of using __get and __set in a PHP class.

class Person {
  private $data = [];
  public function __get($name) {
    return $this->data[$name] ?? null;
  }
  public function __set($name, $value) {
    $this->data[$name] = $value;
  }
}

$person = new Person();
$person->name = 'Alice';
echo $person->name; // Outputs: Alice

intermediate

What happens if you try to access a property that does not exist and __get is not defined?

PHP will trigger a notice about an undefined property and return NULL. Defining __get lets you handle this situation gracefully.

Which magic method is called when you try to read a non-existing property in PHP?

A __get

B __set

C __call

D __construct

The __get method is triggered when reading non-existing properties.

What does the __set method allow you to do?

A Control how to read properties

B Control how to write to properties

C Call methods dynamically

D Initialize the object

The __set method is called when writing to non-existing properties.

If a class has __get and __set methods, what happens when you access a non-existing property?

A __get and __set handle the access

B PHP throws a fatal error

C The property is accessed directly

D The property is ignored

__get and __set allow controlled access to non-existing properties.

What will this code output? class Test { private $data = []; public function __get($name) { return $this->data[$name] ?? 'Not set'; } public function __set($name, $value) { $this->data[$name] = $value; } } $t = new Test(); echo $t->color;

A NULL

B color

C Not set

D Error

Since 'color' is not set, __get returns 'Not set' as defined.

Why might you use __get and __set instead of public properties?

A To make code slower

B To make properties global

C To avoid writing any code

D To control and validate property access

Using __get and __set lets you control how properties are accessed and modified.

Explain how __get and __set magic methods work in PHP and why they are useful.

Think about what happens when you try to read or write a property that is not public.

Write a simple PHP class using __get and __set to store property values in a private array.

Use an array inside the class to save property values dynamically.