PHP名字空间和类中的全局变量问题 [英] PHP Namespace and global variable issue within classes

问题描述

我陷入了这种困惑，我不明白为什么我的HelperClass（）下的全局$错误返回空，我可以验证$ class->错误确实已经充满了数据。

在这种情况下，我没有意识到命名空间是否存在某些问题？请给我一些指示。

以下是一些相关的代码。

在主文件中

  namespace核心; 
 $ class = new ControllerClass（）; 
 $ error = $ class->错误; 
 //验证$错误在这里正确打印
包含ViewFile.php; b 
 
 
 $ b 
 >  $ helper = new HelperClass（）; 
 // __autoload函数负责包含
  

在HelperClass下：

  namespace Core \Skeleton; 
 
 class HelperClass {
 public function __construct（）{
 global $ error; 
 // $ error！= $ class->前面定义的错误
 // $ error在这里为空
} 
   $（$ p 
 
解决方案错误变量从未在'全局'范围内声明。它在一些地方结束了，并被处置掉。
 
 
 
在给它赋值之前声明它是共享的。 
 
 
  namespace Core; 
 $ class = new ControllerClass（）; 
 global $ error; 
 $ error = $ class->错误; 
  
另外，虽然共享变量本身没有问题。名称 $ error 看起来有些过于通用。也许你可以用一个不太具有吸引力或更具结构性的交换变量。  $ GLOBALS [/ var / log] [controller_error] 或者其他数组。
 
I am stuck with this confusion where I don't understand why my global $error under my HelperClass() returns empty, where I could verify that $class->error is indeed filled up with data earlier on.

Is there some sort of issues with namespace in this case that I am not aware about? Please give me some pointers.

Here are some of the codes that are relevant. 

Under Main file
namespace Core;
$class = new ControllerClass();
$error = $class->error;
// verified that $error prints correctly here
include ViewFile.php;
Under ViewFile.php
$helper = new HelperClass();
// __autoload function took care of the include
Under HelperClass:
namespace Core\Skeleton;

class HelperClass {
public function __construct() {
global $error;
// $error != $class->error as defined earlier    
// $error is empty here
}

解决方案
If you're using an autoloader or include your classes from within another helper function, then the $error variable was never declared in the 'global' scope. It ended up in some local, and got disposed.

Declare it shared right before you assign it a value.
namespace Core;
$class = new ControllerClass();
global $error;
$error = $class->error;
Also while there is nothing wrong with shared variables per se. The name $error seems slightly too generic. Maybe you can up with a less ambigious or more structured exchange variable. $GLOBALS["/var/log"]["controller_error"] or something arrayish.

                        
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