Inheritance is a fundamental object-oriented programming concept in PHP where a class (subclass or child class) can inherit properties and methods from another class (superclass or parent class). It enables code reusability and promotes hierarchical relationships between classes.
Syntax:
// Parent class
class Animal {
public $species;
public function sound() {
return "Animal makes a sound.";
}
}
// Child class inheriting from Animal
class Dog extends Animal {
public function sound() {
return "Dog barks.";
}
}
Explanation: To implement inheritance in PHP, use the extends keyword followed by the name of the parent class. The child class inherits all public and protected properties and methods from the parent class.
Accessing Parent Class Members:
-
Child classes can access parent class properties and methods using the
parent::keyword.
Constructor in Inheritance:
-
Child classes can have their own constructors, which can optionally call the parent class constructor using
parent::__construct( ).
Single Inheritance:
- PHP supports single inheritance, meaning a class can inherit from only one parent class at a time.
Multiple Inheritance:
- PHP does not support multiple inheritance where a class can inherit from multiple parent classes simultaneously.