问题
I want to use __dir__.
However, I can't find any good tutorial on how to set it up. I have my htdocs in Dropbox.
Does it work something like this?
define(__DIR___, 'd:documents/dropbox/yolo/swag/htdocs/myproject/test/newtest/
testphp/test_new/testincludes/1/new_folder/')
That is the directory where my project is located and it has sub folders. I want to include a file into another file that is in the parent folder.
Should I then just type:
include'__DIR__/warlock.php';
Or do I have to type something like this?
include '___DIR__/wow/newb/guidesfornabz/classes/casters/warlock.php';
回答1:
You can use __DIR__ to get your current script's directory. It has been in PHP only since version 5.3, and it's the same as using dirname(__FILE__). In most cases it is used to include another file from an included file.
Consider having two files in a directory called inc, which is a subfolder of our project's directory, where the index.php file lies.
project
├── inc
│ ├── file1.php
│ └── file2.php
└── index.php
If we do include "inc/file1.php"; from index.php it will work. However, from file1.php to include file2.php we must do an include relative to index.php and not from file1.php (so, include "inc/file2.php";). __DIR__ fixes this, so from file1.php we can do this:
<?php
include __DIR__ . "/file2.php";
To answer your question: to include the file warlock.php that is in your included file's upper directory, this is the best solution:
<?php
include __DIR__ . "/../warlock.php";
来源：https://stackoverflow.com/questions/32537477/how-to-use-dir