<?class SA_class 
{
	function SA_class( $n="Mehdi" ,$a="20")//default name is "mehdi" and age is "20"
	{
		$this->name = $n;
		$this->age=$a;
	}
	function sayHello() 
	{
		print "Hello my name is $this->name and my age is $this->age <BR>";
	}
}
$obj1 = new SA_class("Reza");
$obj2 = new SA_class("Ali","22");
$obj3 = new SA_class();
$obj1->sayHello();
// Hello my name is Reza and my age is 20 
$obj2->sayHello();
// Hello my name is Ali and my age is 22 
$obj3->sayHello();
// Hello my name is Mehdi and my age is 20 
?>