Question

$thisFile = str_replace('\\', '/', __FILE__);
$docRoot = $_SERVER['DOCUMENT_ROOT'];

$webRoot  = str_replace(array($docRoot, 'library/config.php'), '', $thisFile);
$srvRoot  = str_replace('library/config.php', '', $thisFile);

This is how I get the web root and the server root

web root is the folder name where my files belongs, server root is the C:/xampp/htdocs/folder_name

I just want to ask when should I use webroot and server root.

I just notice that if you are referencing a file ex: href or img src, then only web root works but not server root

But, if you require a file, ex. require_once 'file.php'; only server root works not webroot

Answer 1

You are confusing the server path with the URL path.

On your server, the files are stored at C:/xampp/htdocs/folder_name, but according to your web browser, they are at http://localhost/folder_name. When your browser loads the files, it doesn’t know they are in C:/xampp/htdocs/.

NOTE: None of the code you have there will get you the “web root”.

__FILE__ will return the path of the file on your server, like: `C:/xampp/htdocs/include/header.php.

$_SERVER['DOCUMENT_ROOT'] will return you the path on the server where the files are, like: C:/xampp/htdocs/.

To get your “web root”, you need to use $_SERVER['SERVER_NAME']. This will return you example.com (or whatever). You’re probably gonna need to append http(s):// to it.

$serverRoot = $_SERVER['DOCUMENT_ROOT'];
$webRoot = ($_SERVER['HTTPS'] ? 'https://' : 'http://') . $_SERVER['SERVER_NAME'];

You can also just use / as your web root.

<img src='http://example.com/images/wall.png" />

and

<img src='/images/wall.png" />

should be equivalent.

Try to var_dump($_SERVER);, it’ll give you some fun information.

EDIT: Use dirname if you want to get the “sub folder” under the “root folder”. The above will give you the main root.

$serverPath = dirname(__FILE__); // or __DIR__
$webPath = dirname($_SERVER['PHP_SELF']);