PHP require和require_once在相对路径上失败

Question

We have moved our hosting from server which hosted PHP 5.6 to a new server which hosts PHP 7.0. After the migration, we've noticed the following issue:

PHP Warning: include_once(../classes/ClassA.php): failed to open stream: No such file or directory in /var/www/html/addons/addon.php php on line 37

I understand it should work with

include_once __DIR__."/../classes/ClassA.php";

But I don't understand why it worked on previous server and not on new one. Are there any php.ini changes that were allowing it to work without __DIR __ prefix?

Answer 1

Use $_SERVER['DOCUMENT_ROOT'] instead of _DIR_ . Remove the path components ../../ and point absolutely to a file using the $_SERVER variable.

Or

Create a BASEPATH constant with value of absolute path to your site's root directory. Which you can use to absolutely point to an include file. If you move to another server, just update the value of that variable if needed.

Answer 2

try realpath() function..!

include_once realpath(__DIR__."/../classes/ClassA.php");

The realpath() function returns the absolute pathname.

This function removes all symbolic links (like /./ , ' /../ ' and extra ' / ') and returns the absolute pathname.

This function returns FALSE on failure.