[PHP-생코] PHP 7강 - 접근제어자 = 속성의 가시성(property visibility) ※ 캡슐화(encapsulation)

접근 제어자 1 - 개념

 

접근제어자(access modifier) = 속성의 가시성(property visibility) 

캡슐화 달성 수단 중 하나.

 

캡슐화(encapsulation)

객체 사용자에게 필요한 정보/기능만 노출시켜서, 편의성 및 안정성 높이는 작업.

 

접근 제어자 2 (private vs public)

<?php

class MyFileObject{

  private $filename;

  function __construct($fname){

    $this->filename = $fname;

    if(!file_exists($this->filename)){

      die('There is no file '.$this->filename);

    }

  }

  function isFile(){

    return is_file($this->filename);

  }

}

$file = new MyFileObject('data.txt');

// $file = new MyFileObject();

// $file->filename = 'data.txt';

var_dump($file->isFile());

var_dump($file->filename);

?>

 

접근 제어자 3 - (private vs public)

 

<?php

class Person{

  private $name;

  function sayHi(){

    print("Hi, I'm {$this->name}.");

  }

  function setName($_name){

    if(empty($_name)){

      die('I need name');

    }

    $this->name = $_name;

  }

  function getName(){

    return $this->name;

  }

}

$egoing = new Person();

$egoing->setName('egoing');

$egoing->sayHi();

print($egoing->getName());

?>

 

---

접근 제어자 3 (method visibility)

 

<?php

class Person{

  private $name;

  public function sayHi(){

    print("Hi, I'm {$this->name}.");

  }

  public function setName($_name){

    $this->ifEmptyDie($_name);

    $this->name = $_name;

  }

  public function getName(){

    return $this->name;

  }

  private function ifEmptyDie($value){

    if(empty($value)){

      die('I need name');

    }

  }

}

$egoing = new Person();

$egoing->setName('egoing');

$egoing->sayHi();

print($egoing->getName());

?>

 

https://opentutorials.org/module/6/15730

PS.

 

Visibility 

https://www.php.net/manual/en/language.oop5.visibility.php

 

접근제어자

https://homzzang.com/b/php-1065