PHP ʖ²ἯTH º󍋼/A LXXVI. Object property and method call overloading ½鉜 The purpose of this extension is to allow overloading of object property access and method calls. Only one function is defined in this extension, overload() which takes the name of the class that should have this functionality enabled. The class named has to define appropriate methods if it wants to have this functionality: __get(), __set() and __call() respectively for getting/setting a property, or calling a method. This way overloading can be selective. Inside these handler functions the overloading is disabled so you can access object properties normally. ¾¯¸漯B Шdz ΞШ͢²¿¿⎄¼þ¾ͿɒԼӈ뱾)չģ¿鵄֧³֡£ °²װ PHP µĠWindows °汾ґ¾­Ěփ¸À©չģ¿鵄֧³֡£ĺΞШ¼Ӕ؈κθ½¼ӵĀ©չ¿⼴¿Ɋ¹ӃբЩº¯ʽ¡£ ע: Builtin support for overload is available with PHP 4.3.0. ԋАʱŤփ ¸À©չģ¿鎴¶¨ҥȎºΉ薃ָn¡£ ׊Դ Ѝ Ԥ¶¨ҥ³£ ¸À©չģ¿鎴¶¨ҥȎºγ£¡£ ·¶= =ד 1. Overloading a PHP class ?php class OO {var $a = 111; var $elem = array('b' = 9, 'c' = 42); // Callback method for getting a property function __get($prop_name, $prop_value) {if (isset($this- elem[$prop_name])) {$prop_value = $this- elem[$prop_name]; return true;} else {return false;}} // Callback method for setting a property function __set($prop_name, $prop_value) {$this- elem[$prop_name] = $prop_value; return true;}} // Here we overload the OO object overload('OO'); $o = new OO; print "\$o- a: $o- a\n"; // print: $o- a: print "\$o- b: $o- b\n"; // print: $o- b: 9 print "\$o- c: $o- c\n"; // print: $o- c: 42 print "\$o- d: $o- d\n"; // print: $o- d: // add a new item to the $elem array in OO $o- x = 56; // instantiate stdclass (it is built-in in PHP 4) // $val is not overloaded! $val = new stdclass; $val- prop = 555; // Set "a" to be an array with the $val object in it // But __set() will put this in the $elem array $o- a = array($val); var_dump($o- a[0]- prop);? ¾¯¸漯B As this is an experimental extension, not all things work. There is no __call() support currently, you can only overload the get and set operations for properties. You cannot invoke the original overloading handlers of the class, and __set() only works to one level of property access. Ŀ¼ overload -- Enable property and method call overloading for a class º󍋼/A ưµ㼯A ob_start ɏһ¼¶ overload