Php幻术函数学习与应用 _construct() _destruct() _get()等

<span style="background-color: #ffffff;">class Test{function __construct(){echo "before";}}$t = new Test();</span>

<span style="background-color: #ffffff;"><?class Test{    function Test(){echo "end2";}function __construct(){echo "end";}}$t = new Test();</span>

<span style="background-color: #ffffff;">class Test{function __destruct(){echo "end";}}$t = new Test();</span>

<span style="background-color: #ffffff;">class Test{public function __get($key){echo $key . " 不存在";}}$t = new Test();echo $t->name;</span>

<span style="background-color: #ffffff;">class Test{public function __set($key,$value){echo '对'.$key . "附值".$value;}}$t = new Test();$t->name = "aninggo";</span>

<span style="background-color: #ffffff;">class Test{public function __call($Key, $Args){echo "您要调用的 {$Key} 方法不存在。你传入的参数是：" . print_r($Args, true);}}$t = new Test();$t->getName(aning,go);</span>

<span style="background-color: #ffffff;">class Test{public function __toString(){return "打印 Test";}}$t = new Test();echo $t; </span>

<span style="background-color: #ffffff;">class Test{public function __clone(){echo "我被复制了！";}}$t = new Test();$t1 = clone $t;</span>

<span style="background-color: #ffffff;">Object serializationCODE: [Copy to clipboard]--------------------------------------------<?php class User { public $name; public $id; function __construct() { //give user a unique ID 赋予一个不同的ID $this->id = uniqid(); } function __sleep() { //do not serialize this->id 不串行化id return(array("name")); } function __wakeup() { //give user a unique ID $this->id = uniqid(); } } //create object 建立一个对象 $u = new User; $u->name = "Leon"; //serialize it 串行化 注意不串行化id属性,id的值被抛弃 $s = serialize($u); //unserialize it 反串行化 id被重新赋值 $u2 = unserialize($s); //$u and $u2 have different IDs $u和$u2有不同的ID print_r($u); print_r($u2); ?></span>

<span style="background-color: #ffffff;"><?phpclass A {public static function __set_state($args) {        $obj = new A();        foreach($args as $k=>$v)        {             $obj->$k = $v;        }        return $obj;    }}$a = new A;$a->name = 'cluries';$a->sex = 'female';eval('$b = ' . var_export($a, true) . ';');print_r($b);?></span>

<span style="background-color: #ffffff;">object(A)#2 (2) {         ["name"]=>  string(7) "cluries"         ["sex"]=>  string(6) "female"}</span>

<span style="background-color: #ffffff;">The __invoke method is called when a script tries to call an object as a function.</span>

<span style="background-color: #ffffff;"><?phpclass CallableClass {   function __invoke($x)   {        var_dump($x);}   }$obj = new CallableClass;$obj(5);var_dump(is_callable($obj));?></span>

<span style="background-color: #ffffff;">int(5)bool(true)</span>