我可以使用私有实例方法作为回调吗？

问题描述：

我的特定情况包括在私人方法中使用正则表达式进行一些文本转换。私有方法调用preg_replace_callback，但似乎回调需要对对象是公共的，所以我坚持打破私人世界，并暴露实施细节，而不是。

My particular scenario involves doing some text transformation using regular expressions within a private method. The private method calls preg_replace_callback, but is seems that callbacks need to be public on objects, so I'm stuck breaking out of the private world and exposing implementation details when I'd rather not.

所以，简而言之：我可以使用一个实例方法作为回调而不会丢失封装吗？

So, in a nutshell: Can I use an instance method as a callback without losing encapsulation?

谢谢。

答

是的，你似乎可以：

<?php

//this works
class a {
   private function replaceCallback($m) { return 'replaced'; }

   public function test() {
        $str = " test test ";
        $result = preg_replace_callback('/test/', array($this, 'replaceCallback'), $str);
        echo $result;
   } 
}

$a = new a();
$a->test();


//this doesn't work
$result = preg_replace_callback('/test/', array(new a(), 'replaceCallback'), ' test test ');    
echo $result;

所以看来 preg_replace_callback（）或PHP的回调机制，知道调用它的范围。

So it seems that preg_replace_callback(), or PHP's callback mechanism, is aware of the scope in which it was called.

在5.2.8上测试

我可以使用私有实例方法作为回调吗？

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