Using PHP __DIR__

PHP __DIR__  returns the current working directory, its usage is common when including files as you don’t have to dynamically define the directory each time.

Simply running

echo __DIR__;

Will output the full directory up to where the script was run from.

Take this directory structure example:

root
├── dir1
├── dir2
│ └── functions
│ │  └── display.php
│ │  └── database.php
│ └── index.php
└── index.php

dir2/index.php:

<?php
include __DIR__ . "/functions/database.php";
include __DIR__ . "/functions/display.php";

as using __DIR__ here is: root/dir2

You can also use /../ to go up one level after using __DIR__

include __DIR__ . "/../somedir/file.php";

Using __DIR__ has its benefits when working in a larger project that has a deep folder structure.

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