Path variables in PHP
Many of you develop php applications for multiple server environment. Webserver environment may be different, have different directory structure, so you have to use paths very carefully. For example in file upload script, you manually write absolute path of image directory, the application may not work on other server. To avoid this you should use inbuilt php path variables. I am posting summary of all php related path variables.
Operation: Extract file name from path
Function: string basename ( string $path [, string $suffix ] )
Example:
$path = /opt/lampp/htdocs/demo/test.php;
echo basename($path);
Output: test.php
Operation: Get web server root path
Variable: $HTTP_SERVER_VARS[“DOCUMENT_ROOT“]
Example:
echo $HTTP_SERVER_VARS[“DOCUMENT_ROOT“];
Output: /opt/lampp/htdocs
Operation: Get current script full path (including document root path)
Code: $HTTP_SERVER_VARS[“SCRIPT_FILENAME“]
Example:
echo $HTTP_SERVER_VARS[“SCRIPT_FILENAME“];
Output: /opt/lampp/htdocs/test.php
Operation: Get current script name (relative to root)
Variable: $HTTP_SERVER_VARS[“PHP_SELF“]
Example:
echo $HTTP_SERVER_VARS[“PHP_SELF“];
Output: test.php
Operation: Get current script name (relative to root)
Variable: $HTTP_SERVER_VARS[“PHP_SELF“]
Example:
echo $HTTP_SERVER_VARS[“PHP_SELF“];
Output: test.php
Operation: Convert relative path to absolute path
Function: string realpath ( string $path )
Example:
echo realpath(‘../images’);
Output: /opt/lampp/htdocs/images
Operation: Get all file details
Function: mixed pathinfo ( string $path [, int $options= PATHINFO_DIRNAME | PATHINFO_BASENAME | PATHINFO_EXTENSION | PATHINFO_FILENAME ] )
Example:
$info = pathinfo($_SERVER[‘PHP_SELF’]);
print_r($info);
Output:
Array
(
[dirname] => /abhi
[basename] => EmptyPHP.php
[extension] => php
[filename] => EmptyPHP
)