المتغيرات فائقة النطاق — $_GET و$_POST

<?php
// Basic info
echo $_SERVER['REQUEST_METHOD'];    // GET or POST
echo $_SERVER['REQUEST_URI'];       // /myphp/page.php?id=1
echo $_SERVER['HTTP_HOST'];         // localhost
echo $_SERVER['SERVER_NAME'];       // localhost
echo $_SERVER['SERVER_PORT'];       // 80
echo $_SERVER['REMOTE_ADDR'];       // 127.0.0.1 (user's IP)
echo $_SERVER['HTTP_USER_AGENT'];   // User's browser info
echo $_SERVER['SCRIPT_NAME'];       // /myphp/page.php
echo $_SERVER['PHP_SELF'];          // /myphp/page.php

// Detect HTTPS
$isHttps = isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] === 'on';

// Build the current full URL
$currentUrl = ($isHttps ? "https" : "http") . "://"
    . $_SERVER['HTTP_HOST']
    . $_SERVER['REQUEST_URI'];
echo $currentUrl;  // http://localhost/myphp/demo.php
?>

http://localhost/search.php?q=PHP&page=2&sort=newest
                              ↑          ↑       ↑
                         $_GET['q'] $_GET['page'] $_GET['sort']

<?php
// search.php
$keyword = $_GET['q'] ?? "No search term provided";
$page    = $_GET['page'] ?? 1;
$sort    = $_GET['sort'] ?? "relevance";

echo "Search term: {$keyword}<br>";
echo "Page {$page}<br>";
echo "Sort by: {$sort}<br>";
?>

<?php
$page = (int)($_GET['page'] ?? 1);
$perPage = 20;

echo "<h3>Products — Page {$page}</h3>";

// Generate pagination links
for ($i = 1; $i <= 5; $i++) {
    $active = ($i == $page) ? "style='font-weight:bold;color:red'" : "";
    echo "<a href='?page={$i}' {$active}>{$i}</a> ";
}
?>

<?php
// Check if this is a POST request
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    $name = trim($_POST['name'] ?? '');
    $message = trim($_POST['message'] ?? '');
    
    if ($name && $message) {
        echo "<h3>Message received!</h3>";
        echo "<p><strong>{$name}:</strong> {$message}</p>";
    } else {
        echo "<p style='color:red'>Please fill in all fields</p>";
    }
}
?>

<form method="POST" action="">
    <p>
        <label>Name:</label>
        <input type="text" name="name" value="<?= $_POST['name'] ?? '' ?>">
    </p>
    <p>
        <label>Message:</label>
        <textarea name="message"><?= $_POST['message'] ?? '' ?></textarea>
    </p>
    <button type="submit">Submit</button>
</form>

GET  →  "Show me page 2 of the catalog"    → Best for queries
POST →  "Here are my login credentials"     → Best for mutations

<?php
// $_REQUEST merges $_GET + $_POST + $_COOKIE
// Don't use it! It's unsafe and you can't tell where the data came from
$unreliable = $_REQUEST['name'] ?? '';
// Always use explicit $_GET or $_POST
?>