找不到带有PHP命名空间的类 [英] Cannot find Class with PHP Namespace

问题描述

我之前曾发布过一些有关在PHP中使用命名空间的问题，从我得到的内容来看，下面的示例代码应该可以正常工作.

I posted some questions previously regarding the use of Namespaces in PHP and from what I got, this example code I have below should be working.

但是，当我尝试像这样在PHP中使用命名空间时，出现错误.按原样运行以下代码时，这是第一个错误...

However I am getting errors when I try to use Namespace in PHP like this. Here is the first error when running the code below as is...

Fatal error: Class 'Controller' not found in E:\Controllers\testing.php on line 6

E:\ Controller \ testing.php文件

E:\Controller\testing.php File

<?php
use \Controller;

include('testcontroller.php');

$controller = new Controller;
$controller->show();
?>

E:\ Controller \ testcontroller.php文件

E:\Controller\testcontroller.php File

<?php
use \Library\Registry;

namespace Controller
{
    class Controller
    {
        public $registry;

        function __construct()
        {
            include('E:\Library\Registry.class.php');
            $this->registry = new Registry;
        }

        function show()
        {
            echo $this->registry;
            echo '<br>Registry was ran inside testcontroller.php<br>';
        }
    }
}
?>

E:\ Library \ Registry.class.php文件

E:\Library\Registry.class.php File

<?php
namespace Library\Registry
{
    class Registry
    {
        function __construct()
        {
            return 'Registry.class.php Constructor was ran';
        }
    }
}
?>

如您所见，我试图使它尽可能简单，只是为了使命名空间部分正常工作.我尝试了不同的变体，但似乎无法弄清楚.

As you can see I tried to make it as simple as possible just to get the Namespace part working. I have tried different variations and cannot seem to figure it out.

推荐答案

即使使用use语句，也需要指定要实例化的类的名称空间.这里有很多示例: http://www.php.net /manual/en/language.namespaces.importing.php

Even when using use statement, you need to specify the namespace of the class you are trying to instantiate. There are a lot of examples here: http://www.php.net/manual/en/language.namespaces.importing.php

为了更好地理解它，我将向您介绍它的工作原理.就您而言，当您执行use \Controller时，整个Controller命名空间将变为可用，但该命名空间中的类将不可用.因此，例如:

To understand it better, I will describe to you how it works. In your case, when you do use \Controller, the whole Controller namespace becomes available to you, but not the classes that are in this namespace. So, for example:

<?php
include('testcontroller.php');

use \Controller;

// Desired class is in namespace!
$controller = new Controller\Controller();

// Error, because in current scope there is no such class
$controller = new Controller();

$controller->show();
?>

另一个例子:

testcontoller.php:

testcontoller.php:

<?php
namespace Some\Path\To\Controller;

class Controller
{
    function __construct()
    {

    }

    function show()
    {
        echo '<br>Was run inside testcontroller.php<br>';
    }
}
?>

testing.php:

testing.php:

<?php
include('testcontroller.php');

use \Some\Path\To\Controller;

// We now can access Controller using only Controller namespace,
// not Some\Path\To\Controller
$controller = new Controller\Controller();

// Error, because, again, in current scope there is no such class
$controller = new Controller();

$controller->show();
?>

如果您想完全导入Controller 类，则需要执行use Controller\Controller-这样的类将在您当前的范围内可用.

If you wish to import exactly the Controller class, you need to do use Controller\Controller - then this class will be accessible in your current scope.

这篇关于找不到带有PHP命名空间的类的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！