The __set Magic Method
The magic method __set is automatically called when trying to assign a value to a property that does not exist or is inaccessible in the current context. The method accepts two parameters: the property name and the value being assigned.
Syntax
public function __set(string $name, mixed $value): void
Example
Let's create a class that will use __set to intercept attempts to assign non-existent properties:
<?php
class User {
private $data = [];
public function __set($name, $value) {
$this->data[$name] = $value;
}
public function getData() {
return $this->data;
}
}
$user = new User();
$user->email = 'test@example.com';
$user->age = 25;
print_r($user->getData());
?>
Execution result:
Array
(
[email] => test@example.com
[age] => 25
)
Example
Using __set for data validation before assignment:
<?php
class Product {
private $price;
public function __set($name, $value) {
if ($name === 'price') {
if (!is_numeric($value) || $value < 0) {
throw new Exception('Invalid price value');
}
$this->price = $value;
}
}
public function getPrice() {
return $this->price;
}
}
$product = new Product();
$product->price = 100;
echo $product->getPrice();
?>
Execution result:
100
