index.php

<?php
ini_set('display_errors', 1);
include 'personne.php';

// New instance of personne class
$personne1 = new Personne();

//Set instance properties
$personne1->setPersonne('Mickael','Lehoux','Orleans','26/06/1983');
//Get instance properties
echo 'Bonjour '.$personne1->getPersonne().'<br/>';

//Set address properties
$personne1->setAddress('Orleans');
//Get address properties
echo 'tu habites à '.$personne1->getAddress().'<br/>';

echo 'tu as '.$personne1->age().' ans';

?>

personne.php

<?php

class Personne {

	private $firstName;
	private $lastName;
	private $address;
	private $dateOfBirth;

	// Setter
	public function setPersonne ($firstName,$lastName,$address,$dateOfBirth){
		$this->firstName = $firstName;
		$this->lastName = $lastName;
		$this->address = $address;
		$this->dateOfBirth = $dateOfBirth;
	}

	//Getter
	public function getPersonne (){
		return $this->firstName.'|'.$this->lastName.'|'.$this->address.'|'.$this->dateOfBirth;

	}
	public function setAddress ($address){
		$this -> address = $address;
	}
	public function getAddress (){
		return $this -> address;
	}

	public function age(){
		$tabDate = explode('/',$this->dateOfBirth);
		$birth = new DateTime($tabDate[2]);
		$now = new DateTime();
		$age = $now->diff($birth);
		return $age->y;
	}

}

?>