从外部文件动态加载函数到类中

Is it possible in php to load a function, say from a external file to include in a class. I'm trying to create a loader for helper functions so that I could call:

是否有可能在PHP中加载一个函数,比如从外部文件中加入一个类。我正在尝试为辅助函数创建一个加载器,以便我可以调用:

$registry->helper->load('external_helper_function_file');

after that it should be able call the function in file like this:

之后它应该能够像这样调用文件中的函数:

$registry->helper->function();

Thanks for any help

谢谢你的帮助

3 个解决方案

#1

Setting aside opinions it it's good OOP design. It's possible even with current version of PHP, although not as clean, as it can be with PHP5.3.

抛开意见,这是一个很好的OOP设计。即使使用当前版本的PHP,它也有可能,尽管不像PHP5.3那样干净。

class Helper {
    /* ... */
    function load($file) {
      include_once($file);
    }
    function __call($functionName, $args) {
       if(function_exists($functionName))  
         return call_user_func_array($functionName, $args);
    }

}

#2

ok, 1st, i agree that this is bad manners. also, in 5.3, you could use the new closure syntax with the __call magic word to use operators as functions (JS style).

好的,1,我同意这是不礼貌的。另外,在5.3中,您可以使用带有__call魔术字的新闭包语法将运算符用作函数(JS样式)。

now, if we want to supply a way of doing this you way, i can think of using create_fnuction, mixed with the __call magic.

现在,如果我们想提供一种方法,我可以考虑使用create_fnuction,与__call魔法混合使用。

basically, you use a regex pattern to get convert the functions into compatible strings, and put themin a private member. than you use the __call method to fetch them. i'm working on a small demo.

基本上,你使用正则表达式模式将函数转换为兼容的字符串,并将minmin作为私有成员。而不是使用__call方法来获取它们。我正在做一个小型演示。

ok, here is the class. i got the inspiration from a class i saw a few weeks ago that used closures to implement JS-style objects:

好的,这是班级。我从几周前看到的类中获得了灵感,它使用闭包来实现JS风格的对象:

/**
 * supplies an interface with which you can load external functions into an existing object
 * 
 * the functions supplied to this class will recive the classes referance as a first argument, and as 
 * a second argument they will recive an array of supplied arguments.
 * 
 * @author arieh glazer <arieh.glazer@gmail.com>
 * @license MIT like 
 */
class Function_Loader{
    /**
     * @param array holder of genarated functions
     * @access protected
     */
    protected $_funcs = array();

    /**
     * loads functions for an external file into the object
     * 
     * a note- the file must not contain php tags.
     * 
     * @param string $source a file's loaction
     * 
     * @access public
     */
    public function load($source){
        $ptrn = '/function[\s]+([a-zA-Z0-9_-]*)[\s]*\((.*)\)[\s]*{([\w\s\D]+)}[\s]*/iU';
        $source = file_get_contents($source);
        preg_match_all($ptrn,$source,$matches);
        $names = $matches[1];
        $vars = $matches[2];
        $funcs = $matches[3];
        for ($i=0,$l=count($names);$i<$l;$i++){
            $this->_funcs[$names[$i]] = create_function($vars[$i],$funcs[$i]);
        }
    }

    public function __call($name,$args){
        if (isset($this->_funcs[$name])) $this->_funcs[$name]($this,$args);
        else throw new Exception("No Such Method $name");
    }
}

limitations- 1st, the source cannot have any php tags. 2nd, functions will always be public. 3rd- we can only mimic $this. what i did was to pass as a 1st argument $this, and the second is the array of arguments (which is a 4th limition). also, you will not be able to access non-public members and methods from within the class. an example for a source file:

限制 - 第1,源不能有任何php标签。 2,功能永远是公开的。 3-我们只能模仿$ this。我做的是作为第一个参数$ this传递,第二个是参数数组(这是第四个限制)。此外,您将无法从班级内访问非公开成员和方法。源文件的示例:

function a($self,$arr=array()){
    //assuming the object has a member called str
    echo $self->str;
}

this was a fun exercise for me, but a bad practice all in all

对我来说这是一个有趣的练习,但总的来说这是一个糟糕的练习

#3

So you want to not just include a file, but include it into an object's scope?

所以你不仅要包含一个文件,还要将它包含在一个对象的范围内?

...

I think you're going about this the wrong way. It makes more sense if the registry object has a series of helper members, which have functions of their own. The net result might look something like this:

我认为你这是错误的做法。如果注册表对象具有一系列具有自己的函数的帮助程序成员,则更有意义。最终结果可能如下所示:

$registry->aHelper->aFunction();
$registry->aDifferentHelper->aDifferentFunction();

With careful use of {} syntax, you should be able to dynamically add member objects to your god object.

仔细使用{}语法,您应该能够动态地将成员对象添加到您的上帝对象。

At this point it's worth noting that a god object is almost invariable an anti-pattern. If you need those functions globally, use a bootstrapping include technique and put then in global scope. If you need to pass that data around, then either pass it to functions as required or store it in a database and retrieve it elsewhere.

在这一点上值得注意的是,一个神的物体几乎是不变的反模式。如果您需要全局这些函数,请使用bootstrapping include技术然后将其置于全局范围内。如果需要传递该数据,则根据需要将其传递给函数,或将其存储在数据库中并在其他地方检索。

I know that god object really looks like a good idea, but I promise you it will make things a mess later on.

我知道上帝对象看起来确实是个好主意,但我保证你以后会把事情搞得一团糟。

#1