Access modifiers in PHP

Access modifiers in class PHP, controls the accessibility(use) of its data members and member function. On this basis, a class in PHP has three access modifiers.

1. public
2. private
3. protected

public Access modifiers

class Student{
 public $marks;
}

$obj =  new Student();
$obj->marks = 60;
echo $obj->$marks;

class Student{
 public $marks;

 function setMarks($m){
      $this->marks = $m;
 }
}

$obj =  new Student();
$obj->setMarks(70);

Private Access modifiers

class Student{
 private $marks;
}

$obj =  new Student();
 // Error, because private members are not accessible outside class
$obj->marks = 60;
echo $obj->$marks;

class Student{
 private $marks;

 private function setMarks($mr){
      $this->marks = $mr;
 }
}

$obj =  new Student();
$obj->setMarks(90); // Error. Private members cannot be accessed.

Protected Access modifiers

class Student{
 protected $marks;
}

$obj =  new Student();
$obj->marks = 60; // Error, because protected members are not accessible outside class
echo $obj->$marks;

class Student{
 protected $marks;

 protected function setMarks($mr){
      $this->marks = $mr;
 }
}

$obj =  new Student();
$obj->setMarks(90); // Error. protected members cannot be accessed.