在PHP中运行时删除一个函数 [英] Removing a function at runtime in PHP

问题描述

我在递归函数中声明了一个如果阻止并且希望该功能仅在该if块中为有效。我不希望这个函数在这个块之外被调用。

我发现了 runkit_function_remove 但 runkit 。有没有另外一种方法呢？

顺便说一句我只支持PHP 5.1.0。

编辑：我知道我的问题是hacky，但这是我想要做的确切的事情：

  if（function_exists （'get_magic_quotes_gpc'）&& @get_magic_quotes_gpc（））
 {
函数stripslashes_deep（$ value）
 {
 return is_array（$ value）？ array_map（'stripslashes_deep'，$ value）：stripslashes（$ value）; 
} 
 
 $ _POST = array_map（'stripslashes_deep'，$ _POST）; 
 $ _GET = array_map（'stripslashes_deep'，$ _GET）; 
 $ _COOKIE = array_map（'stripslashes_deep'，$ _COOKIE）; 
 $ _REQUEST = array_map（'stripslashes_deep'，$ _REQUEST）; 
 
 // runkit_function_remove（'stripslashes_deep'）; 
 
  

因为stripslashes_deep只会在魔术时出现 行情是开启的，当我完成它时，我想摆脱它。我不希望人们依赖一个并不总是 的函数。我希望现在更清楚。非巧克力解决方案的建议也受到欢迎！ 关于函数的PHP手册：

PHP中的所有函数和类都具有全局作用域 - 即使它们是在内部定义的，它们也可以在函数外调用，反之亦然。 [...] PHP不支持函数重载，也不可能取消定义或重定义先前声明的函数。

例外是通过runkit。但是，您可以将您的功能定义为匿名功能， a href =http://de2.php.net/manual/en/function.unset.php =noreferrer> unset 它之后你运行它，例如

  if（function_exists（'get_magic_quotes_gpc'）&& @get_magic_quotes_gpc（））
 $ fn = create_function（'& $ v，$ k'，'$ v = stripslashes（$ v）;'）; 
 array_walk_recursive（array（& $ _ GET，& $ _ POST，& $ _ COOKIE，& $ _ REQUEST），$ fn）; 
 unset（$ fn）; 
 
 $ / code> 

有些评论者正确地指出（但现在PHP中不再有问题） ，你不能在其内部调用一个匿名函数。通过使用 array_walk_recursive ，你可以避开这个限制。就个人而言，我只会创建一个常规函数，而不会为删除它而烦恼。它不会伤害任何人。只要给它一个合适的名字，像 stripslashes_gpc_callback 。

注意： em>

I know this question seems hacky and weird, but is there a way to remove a function at runtime in PHP?

I have a recursive function declared in a "if" block and want that function to be "valid" only in that "if" block. I don't want this function to be callled outside this block.

I found out runkit_function_remove but runkit isn't enabled on my Web host. Is there another way to do that?

BTW I only support PHP 5.1.0.

Edit: I knew my question was hacky but here is the exact thing I want to do:

if (function_exists('get_magic_quotes_gpc') && @get_magic_quotes_gpc())
{
    function stripslashes_deep($value)
    {
        return is_array($value) ? array_map('stripslashes_deep', $value) : stripslashes($value);
    }

    $_POST = array_map('stripslashes_deep', $_POST);
    $_GET = array_map('stripslashes_deep', $_GET);
    $_COOKIE = array_map('stripslashes_deep', $_COOKIE);
    $_REQUEST = array_map('stripslashes_deep', $_REQUEST);

    //runkit_function_remove('stripslashes_deep');
}

Since "stripslashes_deep" will only live when Magic Quotes are ON, I wanted to get rid of it when I'm done with it. I don't want people to rely on a function that isn't always there. I hope it's clearer now. Non-hacky solution suggestions are welcome too!

解决方案

From the PHP Manual on Functions:

All functions and classes in PHP have the global scope - they can be called outside a function even if they were defined inside and vice versa. [...] PHP does not support function overloading, nor is it possible to undefine or redefine previously-declared functions.

The exception is through runkit. However, you could define your function as an anonymous function and unset it after you ran it, e.g.

if (function_exists('get_magic_quotes_gpc') && @get_magic_quotes_gpc())
    $fn = create_function('&$v, $k', '$v = stripslashes($v);'); 
    array_walk_recursive(array(&$_GET, &$_POST, &$_COOKIE, &$_REQUEST), $fn);
    unset($fn);
}

Some commentors correctly pointed out (but not an issue any longer in PHP nowadays), you cannot call an anonymous function inside itself. By using array_walk_recursive you can get around this limitation. Personally, I would just create a regular function and not bother about deleting it. It won't hurt anyone. Just give it a proper name, like stripslashes_gpc_callback.

Note: edited and condensed after comments

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