How Can I Retrieve the Subclass Name from a Static Method Call in Extended PHP Classes?

How to Retrieve Class Name from Static Calls in Extended PHP Classes

In software engineering, inheritance allows classes to inherit properties and functionality from their parent classes. In PHP, when you extend a class with subclasses, you can access properties and methods defined in the parent class. However, accessing the name of the subclass from within a static method in the parent class can be challenging.

Problem:

Suppose you have a parent class Action and a subclass MyAction that inherits from Action. You wish to develop a method in the Action class that returns the name of the subclass when called statically from within the subclass. However, using the __CLASS__ variable in the parent class always returns the name of the parent class, which is not the desired outcome.

Solution 1: Late Static Bindings (PHP 5.3 ):

PHP 5.3 introduced late static bindings, which resolve the target class for static method calls at runtime rather than during definition. This feature enables the use of the get_called_class() function, which retrieves the name of the class from which a static method is invoked.

For instance:

<code class="php">class Action {
    public static function n() {
        return get_called_class();
    }
}

class MyAction extends Action {

}

echo MyAction::n(); //displays MyAction</code>

In this example, the get_called_class() function returns the name of the subclass MyAction, even though the method is defined in the parent class Action. This approach provides a straightforward solution to the problem.

Solution 2: Dynamic Class Name Retrieval (PHP 5.2 ):

While late static bindings are not available in PHP versions prior to 5.3, there is an alternative method to dynamically retrieve the class name:

<code class="php">class Action {
    public function n() {
        $object = new ReflectionObject($this);
        return $object->getName();
    }
}

class MyAction extends Action {

}

$myAction = new MyAction();
echo $myAction->n(); //displays MyAction</code>

In this approach, we create a ReflectionObject instance for the current object and use the getName() method to retrieve the class name. This solution works in PHP versions back to 5.2 but requires an extra step of creating a reflection object.

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