php - What is the difference between public, private, and protected?

When and why should I use public, private, and protected functions and variables inside a class? What is the difference between them?

Examples:

// Public
public $variable;
public function doSomething() {
  // ...
}

// Private
private $variable;

private function doSomething() {
  // ...
}

// Protected
protected $variable;
protected function doSomething() {
  // ...
}

Answer

You use:

• public scope to make that property/method available from anywhere, other classes and instances of the object.




• private scope when you want your property/method to be visible in its own class only.




• protected scope when you want to make your property/method visible in all classes that extend current class including the parent class.

More: (For comprehensive information)