PHP MVC Globals Variables

Question

I have a little doubt, I understand that using global variables is a bad practice.

I have a small MVC application with php, in which I would like to create a file .. called config.php and inside it, save the global variables that I will use in my classes, example ...

$config = array ();
$config ['db_host'] = 'localhost';

Now, I would like to know what would be the recommended way to include this file in my application .. I have implemented a autoloader, I could include it in this ...

Class Autoload
{
    public function __construct () {
        global $ config;
        require_once 'config.php';
    }
}

But I really do not know if this is a good practice ...

Thank you very much in advance..

Hi, thanks for your quick reply. Could you help me find a better way to do it? I really can not think of another one. Many thanks again? — php_boy
– php_boy, Commented Jun 6, 2017 at 12:59

Ray Paseur · Accepted Answer · 2017-06-06 12:55:48Z

2

Generally speaking it's not a good practice to use globals or singletons. What you want instead is called "dependency injection." This pattern enables you to use mock objects for testing. Some of the philosophy and practice of dependency injection is available in this article. https://iconoun.com/blog/2017/05/05/php-globals-vs-dependencies/

answered Jun 6, 2017 at 12:55

Ray Paseur

2,2042 gold badges14 silver badges17 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

php_boy Over a year ago

Wow! .. excellent article, I am reading, when finished reading it, surely you take my best answer .. Many, many thanks for this excellent article

Lajos Arpad · Accepted Answer · 2017-06-06 13:37:24Z

0

Instead of globals you could create a class, like this

class Autoload {

    public $value1;
    public $value2;
    public static instances = array();

    public static function instantiate($className) {
        if (isset($instances[$className])) {
            return $instances[$className];
        }
        $newInstance = new $className();
        $newInstance->value1 = "foo";
        $newInstance->value2 = "bar";
        return $instances[$className] = $newInstance;
    }
}

And you can inherit this class for more specific cases, for instance, different user types.

edited Jun 6, 2017 at 13:37

answered Jun 6, 2017 at 13:21

Lajos Arpad

80.4k42 gold badges123 silver badges235 bronze badges

Collectives™ on Stack Overflow

PHP MVC Globals Variables

2 Answers 2

1 Comment

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Related