what is the usage of `spl_autoload_extension() `with `spl_autoload_register()`?

Question

I am using spl_autoload_register() function to include all files . What i want that any class having extension .class.php or .php would includes directly. I made below class and register two different function and everything working fine, BUT

I think there is some way so that i need to register only one function to include both extensions together.

please have a look on my function and tell me what i am missing

my folder structure

project
      -classes
           -alpha.class.php
           -beta.class.php
           -otherclass.php
      -includes
           - autoload.php
      -config.inc.php // define CLASS_DIR and include 'autoload.php'

autoload.php

var_dump(__DIR__); // 'D:\xampp\htdocs\myproject\includes' 
var_dump(CLASS_DIR); // 'D:/xampp/htdocs/myproject/classes/' 
spl_autoload_register(null, false);
spl_autoload_extensions(".php, .class.php"); // no use for now
/*** class Loader ***/
class AL
{
     public static function autoload($class)
     {
          $filename = strtolower($class) . '.php';
          $filepath = CLASS_DIR.$filename;
          if(is_readable($filepath)){
              include_once $filepath;
          }
//          else {
//                trigger_error("The class file was not found!", E_USER_ERROR);
//            }
    }

    public static function classLoader($class)
    {
        $filename = strtolower($class) . '.class.php';
        $filepath = CLASS_DIR . $filename;
        if(is_readable($filepath)){
              include_once $filepath;
          }
    }

}
spl_autoload_register('AL::autoload');
spl_autoload_register('AL::classLoader');

Note : there is no effect on line spl_autoload_extensions(); . why?

i also read this blog but did not understand how to implement.

Answer 1

There is nothing wrong with the way you do it. Two distinctive autoloaders for two kinds of class files are fine, but I would give them slightly more descriptive names ;)

Note : there is no effect on line spl_autoload_extensions(); . why?

This only affects the builtin-autoloading spl_autoload().

Maybe it's easier to use a single loader after all

 public static function autoload($class)
 {
      if (is_readable(CLASS_DIR.strtolower($class) . '.php')) {
          include_once CLASS_DIR.strtolower($class) . '.php';
      }  else if (is_readable(CLASS_DIR.strtolower($class) . '.class.php')) {
          include_once CLASS_DIR.strtolower($class) . '.class.php';
      }
}

You may also omit the whole class

spl_autoload_register(function($class) {
    if (is_readable(CLASS_DIR.strtolower($class) . '.php')) {
        include_once CLASS_DIR.strtolower($class) . '.php';
    }  else if (is_readable(CLASS_DIR.strtolower($class) . '.class.php')) {
        include_once CLASS_DIR.strtolower($class) . '.class.php';
    }
});

Answer 2

Maybe this will help:

http://php.net/manual/de/function.spl-autoload-extensions.php

Jeremy Cook 03-Sep-2010 06:46

A quick note for anyone using this function to add their own autoload extensions. I found that if I included a space in between the different extensions (i.e. '.php, .class.php') the function would not work. To get it to work I had to remove the spaces between the extensions (ie. '.php,.class.php'). This was tested in PHP 5.3.3 on Windows and I'm using spl_autoload_register() without adding any custom autoload functions.

Hope that helps somebody.