Secure Form Handling & Data Sanitization
User input must never be trusted. PHP provides robust filtering tools such as filter_input() and htmlspecialchars() to prevent Cross-Site Scripting (XSS) attacks.
php Example
<?php
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
$email = filter_input(INPUT_POST, 'email', FILTER_VALIDATE_EMAIL);
$name = trim(htmlspecialchars($_POST['name'] ?? '', ENT_QUOTES, 'UTF-8'));
if (!$email) {
$error = 'Please provide a valid email address.';
} else {
echo "Welcome, " . $name . "!";
}
}