命名空间和spl_autoload_register

Question

I have found several SO questions similar to mine, but am struggling to find an answer that helps me, plus I'd really like to know the best practice for autoloading classes that exist within namespaces.

My folder structure:

root
-- classes
--- Users
---- Users.class.php

And users.php;

<?php
namespace CompanyName\ProjectName\Users;

class UserMapper
{
    // class code here
}

And my autoload function, which sits in the root folder;

/* autoload classes on instatiation */
spl_autoload_register(function($class)
{
    include $_SERVER['DOCUMENT_ROOT'] . '/classes/' . $class . '.class.php';
}); 

And, let's say I call the user class like so;

<?php
    new \CompanyName\ProjectName\User();

Warning: include(/Applications/XAMPP/xamppfiles/htdocs/test_tool/classes/CompanyName\ProjectName\User.class.php): failed to open stream: No such file or directory in...etc

To use spl_autoload_register, do I need to map my folder structure to my namespace structure? I would prefer not to do this as I like to have my classes in the same folder, with sub folders within.

Or do I add extra code to my autoload function?

I have also searched the php manual, and there is no working namespace example, which I find very strange.

Any help would be much appreciated.

Thanks in advance.

Answer 1

Disclaimer: I am a beginer at php, my answer may not be correct but i'm confident examining and testing the example bellow will help clarify the use of Namespaces with spl_autoload_register for any beginner like me.

Consider this folder structure :

• root/ contains index.php.
• root/model/ contains A.php & AA.php

A.php :

?php 

namespace company\model;

use \company\model\A;

class A 
{
    public function speak()
    {
        echo 'hello world! ';
    }
}

AA.php :

?php 

namespace company\model;

use \company\model\A;

require_once 'A.php';

class AA extends A 
{
    public function shout()
    {
        echo 'HELLO WOORLD!!!';
    }
}

index.php :

<?php 
    namespace company; 

    use \company\model\A;

    function classLoader ($className)
    {
        if (file_exists($className.'.php'))
        {
            require_once $className.'.php';
        } else {
            $className = str_replace('\\', '/', $className);
            $className = str_replace('company/', '', $className);
            if (file_exists($className.'.php'))
                require_once $className.'.php';
            else
                throw new EXCEPTION('classLoader could not find '.$className.'.php .');
      }
    }
    spl_autoload_register(classLoader);

    $obj = new A; 
    //we dont need to write ($obj = new \company\model\A;) 
    //because of statement at line 4
    $obj->speak();

    echo '<br/>';

    $objA = new \company\model\AA;  
    $objA->shout();

    echo '<br/>';

    class AB extends \company\model\AA  
    {
        public function doBoth()
        {
            $this->speak();
            $this->shout();
        }
    }

    $objB = new AB;
    $objB->doBoth();

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