<?php
    class User
    {
        private $name;
        private $age;

        public function __set($property,$value){
            switch($property){
                case 'name':
                    if($value != ''){
                        $this -> $property = $value;
                    }
                break;
                case 'age':
                    if($value >= 0 && $value<= 70){
                        $this -> $property = $value;
                    }
                break;
            }
        }
        public function show(){
            return $this -> name." ".$this -> age;
        }
        public function __get($property){
            return $this -> property;
        }
    }
    $user = new User;
    $user -> name = "Nikita";
    $user -> age = 17;
    echo $user -> name;
?>