PHP: Information on a Web Page

In the first part of this article, we saw how to parse part of a URL, and the parameters involved in the case where one deals with a string.

This part shows how to get the same information, including obtaining data from a form to pass to a PHP script.

Comparison with parse_url

Data on the script or PHP page are obtained with the predefined variable $_SERVER and a list of keys corresponding to the information sought, which are given in the table below.

Take note that the domain name is given directly by the user. In our example, it is www.scriptol.com.

Data
parse_url
Keys for $_SERVER
Full URL
__FILE__
domain + REQUEST_URI
Protocol
scheme
SERVER_PROTOCOL
Domain
host
user constant
Directory and file
path
SCRIPT_NAME
Anchor in the page
fragment
-
Parameters
query
QUERY_STRING
Port
-
-
Login
user
Treated separately
Password
pass
Treated separately
Correspondence between parse_url and $_SERVER

Differences:

Using the predefined variable

Example:

$protocol = $_SERVER[SERVER_PROTOCOL];

The list of keys is provided in the PHP manual under the heading: "predefined variables."

Retrieving data from an HTML form

Example:

$parameters = $_SERVER[QUERY_STRING];

parse_str($parameters, $data);
print_r($data);

$data is an associative array, where keys are variables given as parameters, and values, the content of these variables.

See the first part of the article for more details.

Sources and download