How do PHP_SELF, PATH_INFO, SCRIPT_NAME, and REQUEST_URI Differ in Determining a Script\'s Address?

Determining a Script's Address in PHP: PHP_SELF, PATH_INFO, SCRIPT_NAME, REQUEST_URI

When developing PHP applications, understanding the differences between PHP_SELF, PATH_INFO, SCRIPT_NAME, and REQUEST_URI is crucial to determine a script's address reliably.

PHP_SELF represents the full URL of the script, including the query string. In most cases, it's the most reliable option for retrieving a script's full address. However, if a request goes through mod_rewrite directives, PHP_SELF may not reflect the actual requested URL.

PATH_INFO stores the portion of the URL after the script name. This information becomes available when using mod_rewrite, but it may be empty in certain situations.

SCRIPT_NAME contains the actual filename of the script being executed, excluding any path information. Unlike PHP_SELF, SCRIPT_NAME is not affected by mod_rewrite.

REQUEST_URI captures the complete request URI, including the path, query string, and any anchor fragments. It's useful when working with proxy servers or when dealing with redirects.

To illustrate the differences, here are a few examples:

• Example 1: When using mod_rewrite to redirect http://example.com/test.php/foo/bar to http://example.com/index.php/test.php/foo/bar:

  • PHP_SELF: /test.php/foo/bar
  • SCRIPT_NAME: /test.php
  • PATH_INFO: /foo/bar

• Example 2: When using a non-empty query string in http://example.com/test.php?foo=bar:

  • PHP_SELF: /test.php?foo=bar
  • SCRIPT_NAME: /test.php
  • REQUEST_URI: /test.php?foo=bar

• Example 3: When using mod_rewrite to redirect http://example.com/test.php to http://example.com/test2.php:

  • PHP_SELF: /test.php
  • SCRIPT_NAME: /test2.php
  • REQUEST_URI: /test.php

By understanding these differences, you can select the most appropriate variable for your specific needs, ensuring reliable access to a script's address, regardless of web server configuration or URL manipulation.

The above is the detailed content of How do PHP_SELF, PATH_INFO, SCRIPT_NAME, and REQUEST_URI Differ in Determining a Script\'s Address?. For more information, please follow other related articles on the PHP Chinese website!