<?php 
   class overloader 
   { 
       private $properties = array(); 

       function __get($property_name) 
       { 
           if(isset($this->properties[$property_name])) 
           { 
               return($this->properties[$property_name]); 
           } 
           else 
           { 
               return(null); 
           } 
       } 

       function __set(value) 
       { 
           $this->properties[value; 
       } 

       function __call(args) 
       { 
           print("invoking $function_name()<br>\n"); 
           print("arguments: "); 
           print_r($args); 

           return(true); 
       } 
   } 
   $o = new overloader(); 

   //invoke __set() 给一个不存在的属性变量赋值,激活__set() 
   $o->dynaprop = "dynamic content"; 

   //invoke __get() 激活__get() 
   print($o->dynaprop . "<br>\n"); 

   //invoke __call() 激活__call() 
   $o->dynamethod("leon", "zeev"); 
?>