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PHP Object-Oriented PHP Basics (Retired) Inheritance, Interfaces, and Exceptions Inheritance to Interfaces

what is the keyword to use an interface of a class? Its it extends?

or is it implements

1 Answer

Sergey Podgornyy
Sergey Podgornyy
20,660 Points

Use implements when you define class, which depends on Interfaces:

interface A
{
    public function foo();
}

interface B
{
    public function bar();
}

class C implements A, B {...}

Use extends when you define class, which depends on other class:

class A {...}
class B extends A {...}

Or when you define Interface, which depends on Interfaces:

interface A
{
    public function foo();
}

interface B
{
    public function bar();
}

interface C extends A
{
    public function foofoo();
}

interface D extends A, B
{
    public function foobar();
}