The __call() method is triggered when an inaccessible or undefined method is called on an object, allowing custom handling by accepting the method name and arguments, as shown when calling undefined methods like sayHello(). 2. The __get() method is invoked when accessing inaccessible or non-existent properties, enabling dynamic property retrieval, such as accessing name from the internal $data array in the Person class. 3. Both magic methods enhance flexibility by letting objects respond intelligently to undefined operations, but should be used cautiously to maintain code clarity and debuggability.

Magic methods in PHP are special built-in methods that start with two underscores (__) and are automatically triggered in response to specific events or operations. They allow developers to define custom behaviors for common PHP operations like calling undefined methods, accessing properties, object instantiation, and more.

Two commonly used magic methods are __call() and __get().

__call()

This method is triggered when an inaccessible or undefined method is called on an object (either public method that doesn't exist, or a private/protected method being accessed from outside).

Syntax:

public function __call($methodName, $arguments)

• $methodName: The name of the called method.
• $arguments: An array of arguments passed to the method.

Example:

class User {
    private function greet($name) {
        echo "Hello, $name!";
    }

    public function __call($method, $args) {
        echo "Method '$method' does not exist or is not accessible.<br>";
        echo "You tried to pass: " . implode(', ', $args);
    }
}

$user = new User();
$user->greet('Alice');        // This won't trigger __call() because method exists but is private
$user->sayHello('Bob');       // Triggers __call()

Output:

Method 'sayHello' does not exist or is not accessible.
You tried to pass: Bob

Note: Since greet() is private, calling it directly from outside the class would result in a fatal error, not __call(). But if the method were simply undefined, __call() would handle it gracefully.

__get()

This magic method is invoked when trying to access an inaccessible or undefined property (i.e., a private/protected property or a property that doesn't exist).

Syntax:

public function __get($propertyName)

• $propertyName: The name of the property being accessed.

Example:

class Person {
    private $data = [
        'name' => 'John',
        'age' => 30
    ];

    public function __get($property) {
        if (array_key_exists($property, $this->data)) {
            return $this->data[$property];
        } else {
            echo "Property '$property' does not exist.";
            return null;
        }
    }
}

$person = new Person();
echo $person->name;   // Output: John
echo $person->email;  // Output: Property 'email' does not exist.

Here, __get() allows controlled access to the internal $data array as if they were real properties.

These magic methods are useful for implementing flexible APIs, dynamic property/method handling, or creating "lazy" loading behavior. But they should be used carefully to avoid making code hard to debug or understand.

Basically, they let your objects respond intelligently when someone tries to use something that isn’t directly available.

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