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phpinclude-path

Best way to include file in PHP?


I'm currently developping a PHP web application and I would like to know what is the best manner to include files (include_once) in a way where the code it is still maintanable. By maintanable I mean that if I want to move a file, It'd be easy to refactor my application to make it work properly.

I have a lot of files since I try to have good OOP practices (one class = one file).

Here's a typical class structure for my application:

namespace Controls
{
use Drawing\Color;

include_once '/../Control.php';

class GridView extends Control
{
    public $evenRowColor;

    public $oddRowColor;

    public function __construct()
    {
    }

    public function draw()
    {
    }

    protected function generateStyle()
    {
    }

    private function drawColumns()
    {
    }
}
}

Solution

  • It depends on what you are trying to accomplish exactly.

    If you want to have a configurable mapping between files and the directories in which they reside you need to work out a path abstraction and implement some loader functions to work with that. I 'll do an example.

    Let's say we will use a notation like Core.Controls.Control to refer to the (physical) file Control.php which will be found in the (logical) directory Core.Controls. We 'll need to do a two-part implementation:

    1. Instruct our loader that Core.Controls is mapped to the physical directory /controls.
    2. Search for Control.php in that directory.

    So here's a start:

    class Loader {
        private static $dirMap = array();
    
        public static function Register($virtual, $physical) {
            self::$dirMap[$virtual] = $physical;
        }
    
        public static function Include($file) {
            $pos = strrpos($file, '.');
            if ($pos === false) {
                die('Error: expected at least one dot.');
            }
    
            $path = substr($file, 0, $pos);
            $file = substr($file, $pos + 1);
    
            if (!isset(self::$dirMap[$path])) {
                die('Unknown virtual directory: '.$path);
            }
    
            include (self::$dirMap[$path].'/'.$file.'.php');
        }
    }
    

    You would use the loader like this:

    // This will probably be done on application startup.
    // We need to use an absolute path here, but this is not hard to get with
    // e.g. dirname(_FILE_) from your setup script or some such.
    // Hardcoded for the example.
    Loader::Register('Core.Controls', '/controls');
    
    // And then at some other point:
    Loader::Include('Core.Controls.Control');
    

    Of course this example is the bare minimum that does something useful, but you can see what it allows you to do.

    Apologies if I have made any small mistakes, I 'm typing this as I go. :)