Does PHP support multiple inheritances? Explain with Examples

No, PHP does not support multiple inheritances directly, meaning a class cannot inherit properties and methods from more than one base class. However, PHP does support a limited form of multiple inheritances through the use of interfaces and traits.

1. Interfaces: Interfaces allow you to declare methods without defining them within the interface. Any class that implements an interface must provide concrete implementations for all the methods declared in the interface. A class can implement multiple interfaces, achieving a form of multiple inheritance. Here's an example:

php code

interface Car {

    public function startEngine();

}

interface Bicycle {

    public function pedal();

}

class HybridVehicle implements Car, Bicycle {

    public function startEngine() {

        echo "Hybrid vehicle engine started.";

    }

    public function pedal() {

        echo "Hybrid vehicle pedaling.";

    }

}

$hybridCar = new HybridVehicle();

$hybridCar->startEngine();  // Output: Hybrid vehicle engine started.

$hybridCar->pedal();        // Output: Hybrid vehicle pedaling.

In this example, the HybridVehicle class implements both the Car and Bicycle interfaces, allowing it to use methods from both interfaces.

2. Traits: Traits are a mechanism in PHP that allows you to reuse methods in several independent classes. Traits are similar to classes, but they are intended to group functionality in a fine-grained and consistent way. A class can use multiple traits, providing a form of multiple inheritance. Here's an example:

php code

trait Engine {

    public function startEngine() {

        echo "Engine started.";

    }

}

trait Wheels {

    public function rotateWheels() {

        echo "Wheels rotating.";

    }

}

class Car {

    use Engine, Wheels;

}

$myCar = new Car();

$myCar->startEngine();   // Output: Engine started.

$myCar->rotateWheels();  // Output: Wheels rotating.

In this example, the Car class uses both the Engine and Wheels traits, allowing it to access methods from both traits.

So, while PHP does not support multiple inheritances in the traditional sense, you can achieve similar functionality using interfaces and traits.