spl_autoload_register not working

Question

I have created 5 folders containing 5 classes (Ad_Class, Blocked_Class, Friend_Class, Image_Class, Profile_Class) in the main directory. I also created the respective classes within the mentioned folders with the exact name as the folders. i.e. if folder name is Ad_Class then the class within the folder is also the same as the folder name as in "class Ad_Class.

In the index.php file I wrote the following code:

function Ad_Class($name)
{
    include "Ad_Class/$name.php";
}
function Blocked_Class($name)
{
    include "Blocked_Class/$name.php";
}
function Friend_Class($name)
{
    include "Friend_Class/$name.php";
}
function Image_Class($name)
{
    include "Image_Class/$name.php";
}
function Profile_Class($name)
{
    include "Profile_Class/$name.php";
}

spl_autoload_register("Ad_Class");
spl_autoload_register("Blocked_Class");
spl_autoload_register("Friend_Class");
spl_autoload_register("Image_Class");
spl_autoload_register("Profile_Class");

$a = new Ad_Class;
$b = new Blocked_Class;
$c = new Blocked_Class;
$d = new Image_Class;
$e = new Profile_Class;

After executing the above code I get the below warnings:

Warning: include(Ad_Class/Blocked_Class.php): failed to open stream: No such file or directory in C:\Users\Robert\Documents\web development\xampp\htdocs\xampp\web_development\development.php on line 4

Warning: include(): Failed opening 'Ad_Class/Blocked_Class.php' for inclusion (include_path='.;C:\Users\Robert\Documents\web development\xampp\php\PEAR') in C:\Users\Robert\Documents\web development\xampp\htdocs\xampp\web_development\development.php on line 4

Warning: include(Ad_Class/Image_Class.php): failed to open stream: No such file or directory in C:\Users\Robert\Documents\web development\xampp\htdocs\xampp\web_development\development.php on line 4

Warning: include(): Failed opening 'Ad_Class/Image_Class.php' for inclusion (include_path='.;C:\Users\Robert\Documents\web development\xampp\php\PEAR') in C:\Users\Robert\Documents\web development\xampp\htdocs\xampp\web_development\development.php on line 4

Warning: include(Blocked_Class/Image_Class.php): failed to open stream: No such file or directory in C:\Users\Robert\Documents\web development\xampp\htdocs\xampp\web_development\development.php on line 8

Warning: include(): Failed opening 'Blocked_Class/Image_Class.php' for inclusion (include_path='.;C:\Users\Robert\Documents\web development\xampp\php\PEAR') in C:\Users\Robert\Documents\web development\xampp\htdocs\xampp\web_development\development.php on line 8

Warning: include(Friend_Class/Image_Class.php): failed to open stream: No such file or directory in C:\Users\Robert\Documents\web development\xampp\htdocs\xampp\web_development\development.php on line 12

Warning: include(): Failed opening 'Friend_Class/Image_Class.php' for inclusion (include_path='.;C:\Users\Robert\Documents\web development\xampp\php\PEAR') in C:\Users\Robert\Documents\web development\xampp\htdocs\xampp\web_development\development.php on line 12

Warning: include(Ad_Class/Profile_Class.php): failed to open stream: No such file or directory in C:\Users\Robert\Documents\web development\xampp\htdocs\xampp\web_development\development.php on line 4

Warning: include(): Failed opening 'Ad_Class/Profile_Class.php' for inclusion (include_path='.;C:\Users\Robert\Documents\web development\xampp\php\PEAR') in C:\Users\Robert\Documents\web development\xampp\htdocs\xampp\web_development\development.php on line 4

Warning: include(Blocked_Class/Profile_Class.php): failed to open stream: No such file or directory in C:\Users\Robert\Documents\web development\xampp\htdocs\xampp\web_development\development.php on line 8

Warning: include(): Failed opening 'Blocked_Class/Profile_Class.php' for inclusion (include_path='.;C:\Users\Robert\Documents\web development\xampp\php\PEAR') in C:\Users\Robert\Documents\web development\xampp\htdocs\xampp\web_development\development.php on line 8

Warning: include(Friend_Class/Profile_Class.php): failed to open stream: No such file or directory in C:\Users\Robert\Documents\web development\xampp\htdocs\xampp\web_development\development.php on line 12

Warning: include(): Failed opening 'Friend_Class/Profile_Class.php' for inclusion (include_path='.;C:\Users\Robert\Documents\web development\xampp\php\PEAR') in C:\Users\Robert\Documents\web development\xampp\htdocs\xampp\web_development\development.php on line 12

Warning: include(Image_Class/Profile_Class.php): failed to open stream: No such file or directory in C:\Users\Robert\Documents\web development\xampp\htdocs\xampp\web_development\development.php on line 16

Warning: include(): Failed opening 'Image_Class/Profile_Class.php' for inclusion (include_path='.;C:\Users\Robert\Documents\web development\xampp\php\PEAR') in C:\Users\Robert\Documents\web development\xampp\htdocs\xampp\web_development\development.php on line 16

Why is this happening? Can anyone explain?

Update: I found the following code to work. If you have any suggestions please feel free to share!

function ad_class($class)
{
    if(!class_exists($class) && $class == "Ad_Class")
    {
        include "Ad_Class/$class" . ".php";
    }
    elseif(!class_exists($class))
    {
        return;
    }
}

function blocked_class($class)
{
    if(!class_exists($class) && $class == "Blocked_Class")
    {
        include "Blocked_Class/$class" . ".php";
    }
    elseif(!class_exists($class))
    {
        return;
    }
}

function friend_class($class)
{
    if(!class_exists($class) && $class == "Friend_Class")
        {
        include "Friend_Class/$class" . ".php";
    }
    elseif(!class_exists($class))
    {
        return;
    }
}

function image_class($class)
{
    if(!class_exists($class) && $class == "Image_Class")
    {
        include "Image_Class/$class" . ".php";
    }
    elseif(!class_exists($class))
    {
        return;
    }
}

function profile_class($class)
{
        if(!class_exists($class) && $class == "Profile_Class")
    {
        include "Profile_Class/$class" . ".php";
    }
    elseif(!class_exists($class))
    {
        return;
    }
}
spl_autoload_register("ad_class");
spl_autoload_register("blocked_class");
spl_autoload_register("friend_class");
spl_autoload_register("image_class");
spl_autoload_register("profile_class");

$a = new Ad_Class;
$a->ad();

$b = new Blocked_Class;
$b->block();

$c = new Friend_Class;
$c->fr();

$d = new Image_Class;
$d->image();

It produces the following: Advertising Blocked Friend Image

which is nothing more than displaying the class name of the instantiated object to see if the code worked correclty in loading classes.

Answer 1

spl_autoload_register() stacks, so it's going to run all five functions you have defined for each class you try to create, regardless of which class it is. Take this example and rework it to fit your needs:

spl_autoload_register( function($name) {
    if (is_file('/classes/'.$name.'.class.php')) {
        require_once('/classes/'.$name.'.class.php');
    }
});

Checking for the file with is_file() will save the headache of all those No such file or directory warnings. Depending on your file path layout, you might need to expand the anonymous function example I've given with a switch() statement or something like that.