Jina la Sifa kutoka kwenye Safu katika OOP kwa PHP

Wacha sasa tuangalie jinsi ya kurejea kwa sifa ya kitu kwa jina kutoka kwa kipengele cha safu. Acha tuwe na darasa lifuatalo User:

php<?php
  class User
  {
    public $name;
    public $surn;
    
    public function __construct($name, $surn)
    {
      $this->name = $name;
      $this->surn = $surn;
    }
  }
?>

Tuweke kitu cha darasa hili:

php<?php
  $user = new User('john', 'smit');
?>

Acha tupewe safu ya sifa:

php<?php
  $props = ['name', 'surn'];
?>

Sasa tujaribu kuonyesha thamani ya sifa, ambayo imehifadhiwa kwenye kipengele cha sifuri cha safu:

php<?php
  echo $user->$props[0]; // haitafanya kazi hivi
?>

Ili jina changamano la sifa kama hili lifanye kazi, linahitaji kuzingirwa kwa mabano ya kuni, kama ifuatavyo:

php<?php
  echo $user->{$props[0]}; // itaonyesha 'john'
?>

php<?php
  class Employee
  {
    public $name;
    public $salary;
    public $position;
    
    public function __construct($name, $salary, $position)
    {
      $this->name = $name;
      $this->salary = $salary;
      $this->position = $position;
    }
  }
?>

php<?php
  $arr = ['name', 'salary', 'position'];
?>