PHP
Everything with $_REQUEST
Learn to receive GET, POST and cookie data together with $_REQUEST.
Everything with $_REQUEST
The $_REQUEST superglobal merges $_GET, $_POST and $_COOKIE by default. From one place you can reach URL, form and cookie data together.
The merge order follows the request_order php.ini setting; the default is 'GP', meaning GET first then POST overwrites it. When a key clashes, POST wins. In CLI $_REQUEST starts empty.
request_order and clashes
The request_order setting controls the merge order. The default 'GP' means POST writes over GET; 'GPC' lets the cookie win last.
So when the same key appears in both GET and POST, $_REQUEST shows the POST value under the default setting. For security, knowing the source matters; in doubt, using $_GET or $_POST directly is safer.
Exercise Safe access with a param function
Define a function named param; its first parameter is $key, the second is $default with a default value of empty string "". In the body write return $_REQUEST[$key] ?? $default;. Outside the function set $_REQUEST['page'] = "3";. Then call echo param('page') . "\n"; and echo param('missing', '1') . "\n";.
Show example solution
Define function param($key, $default = "") { return $_REQUEST[$key] ?? $default; }, set $_REQUEST['page'] = "3"; outside, then write echo param('page') . "\n"; and echo param('missing', '1') . "\n";.
Example solution:
<?php
// Define param and call it
$_REQUEST['page'] = "3";
function param($key, $default = "") {
return $_REQUEST[$key] ?? $default;
}
echo param('page') . "\n";
echo param('missing', '1') . "\n";
Test yourself
-
Which three superglobals does $_REQUEST merge by default?
- $_GET + $_POST + $_FILES
- $_GET + $_POST + $_COOKIE
- $_GET + $_POST + $_SESSION
- $_POST + $_COOKIE + $_ENV
Show answer
$_GET + $_POST + $_COOKIE — Correct. $_REQUEST merges the $_GET, $_POST and $_COOKIE superglobals.
-
Match each superglobal to its source
- $_GET
- From URL
- $_POST
- From form body
- $_COOKIE
- From cookies
- $_REQUEST
- GET+POST+COOKIE
-
Complete the $_REQUEST access
$id = $_REQUEST[____] ?? 0;
Show answer
$id = $_REQUEST['id'] ?? 0;
Next lesson: Summary - Superglobals
