使一个全局变量可访问类中的每个函数 [英] Making a global variable accessible for every function inside a class

问题描述

我在全局范围上有一个名为 $ {SYSTEM} 的变量，其中SYSTEM是一个定义的常量。我有很多类的函数需要访问这个变量，我发现它讨厌的声明 global $ {SYSTEM}; 每一次。 / p>

我试着声明一个类变量： public $ {SYSTEM} = $ GLOBALS [SYSTEM]; 一个语法错误是奇怪的，因为我有另一个类，以这种方式声明类变量，似乎工作正常。我唯一能想到的是常数不被识别。

我已经设法使用一个构造函数，但我正在寻找一个更简单的

全局$ {SYSTEM} 变量是一个有很多其他子数组的数组。不幸的是，似乎没有办法使用构造函数...

解决方案

 <？php 
 //你想要的全局数组访问
 $ GLOBALS ['uname'] = array（'kernel-name'=>'Linux'，'kernel-release'=>'2.6.27-11-generic'，'machine' >'i686'）; 
 
 //用于引用全局变量的定义常量var 
 define（_SYSTEM_，'uname'）; 
 
 class Foo {
 
 //你想要访问全局变量的方法var 
 public function bar（）{
 print_r（$ this-> {_ SYSTEM_}）; 
} 
 
 //这里的魔法发生在这里使用php5重载
 public function __get（$ d）{
 return $ GLOBALS [$ d]; 
} 
 
} 
 
 $ foo = new Foo; 
 $ foo> bar（）; 
 
？> 
  

I have a variable on the global scope that is named ${SYSTEM}, where SYSTEM is a defined constant. I've got a lot of classes with functions that need to have access to this variable and I'm finding it annoying declaring global ${SYSTEM}; every single time.

I tried declaring a class variable: public ${SYSTEM} = $GLOBALS[SYSTEM]; but this results in a syntax error which is weird because I have another class that declares class variables in this manner and seems to work fine. The only thing I can think of is that the constant isn't being recognised.

I have managed to pull this off with a constructor but I'm looking for a simpler solution before resorting to that.

---

EDIT The global ${SYSTEM} variable is an array with a lot of other child arrays in it. Unfortunately there doesn't seem to be a way to get around using a constructor...

解决方案

Ok, hopefully I've got the gist of what you're trying to achieve

<?php
    // the global array you want to access
    $GLOBALS['uname'] = array('kernel-name' => 'Linux', 'kernel-release' => '2.6.27-11-generic', 'machine' => 'i686');

    // the defined constant used to reference the global var
    define(_SYSTEM_, 'uname');

    class Foo {

        // a method where you'd liked to access the global var  
        public function bar() {
            print_r($this->{_SYSTEM_});
        }

        // the magic happens here using php5 overloading
        public function __get($d) {
            return $GLOBALS[$d];  
        }

    }

    $foo = new Foo;
    $foo->bar();

?>

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