PHP-php为对象动态添加函数的方法？

Question

想为一个对象动态的添加函数，如下代码错误。不知PHP中如何动态添加方法

$me= new stdClass;
$me->doSomething=function ()
 {
    echo 'I've done something';
 };
$me->doSomething();

//Fatal error: Call to undefined method stdClass::doSomething()

Answer 1

你添加的方法没问题，只是调用错了，不能直接 $me->doSomething();

应该为：
$func = $me->doSomething;
$func();
或者：
call_user_func($me->doSomething);

复制手册上一个例子：

$obj = new StdClass();
$obj->func = function(){
echo "hello";
};
//$obj->func(); // doesn't work! php tries to match an instance method called "func" that is not defined in the original class' signature

// you have to do this instead:
$func = $obj->func;
$func();
// or:
call_user_func($obj->func);

Answer 2

上面的代码类似JS的用法，PHP里不能怎么使用。给个示例：

class Foo
{
public function __call($method, $args)
{
if (isset($this->$method)) {
$func = $this->$method;
$func($args);
}
}
}

$foo = new Foo();
$foo->bar = function () { echo "Hello, this function is added at runtime"; };
$foo->bar();