php return与echo之间的区别详细介绍

<?
class Human{  
private $money = 1000;  
public function showMoney(){    
return $this->money; }}
$money = new Human();
$money->showMoney();
 
?>

<?
class Human{  
private $money = 1000;  
public function showMoney(){    
echo $this->money; }}
$money = new Human(); 
$money->showMoney();
?>

<?
class Human{  
private $money = 1000;  
public function showMoney(){    
return $this->money; }}
$money = new Human();
echo $money->showMoney();
 
?>