When a class is defined by inheriting the existing function of a parent class, it is called inheritance. Here, the child class will inherit all or a few member functions and variables of a parent class. We can define an inherited class by using the extends keyword.
Inheritance has three types: Single, Multiple, and Multilevel Inheritance, but PHP only supports single inheritance, where only one class can be derived from a single parent class.
Example:
<?php
class exm {
public function func1()
{
echo "example of inheritance ";
}
}
class exm1 extends exm {
public function func2()
{
echo "in php";
}
}
$obj= new exm1();
$obj->func1();
$obj->func2();
?>
Output:
example of inheritance in php
The final keyword can be used to prevent method overriding or to prevent class inheritance.
Example:
<?php
final class Employee {
// some code
}
// This will result in error as the final keyword is used
class human extends Employee {
// some code
}
?>
