php urlcode 怎样提高安全性

?PHP?,urlencode() ???????????URL????????????,?????????:

1. ?? rawurlencode() ??:? urlencode() ??,rawurlencode() ?????????,????URL??????,?????????????URL?

$string = "Hello World!";
$encoded_string = rawurlencode($string);
echo $encoded_string; // ??: "Hello World!"

2. ????????????:?????????????????,???????????????PHP???????,? filter_var(),?????????

$user_input = $_POST['username'];
$filtered_input = filter_var($user_input, FILTER_SANITIZE_STRING);

3. ???????(Prepared Statements):????????,?????????????????SQL???????PDO?MySQLi?????????

// ??PDO
$pdo = new PDO('mysql:host=example.com;dbname=testdb', 'username', 'password');
$stmt = $pdo->prepare('INSERT INTO users (username) VALUES (:username)');
$stmt->bindParam(':username', $username);
$username = 'JohnDoe';
$stmt->execute();

// ??MySQLi
$mysqli = new mysqli('example.com', 'username', 'password', 'testdb');
$stmt = $mysqli->prepare('INSERT INTO users (username) VALUES (?)');
$stmt->bind_param('s', $username);
$username = 'JohnDoe';
$stmt->execute();

4. ??HTTP POST??:????HTTP POST?????GET?????????,??POST??????????URL?,?????????????

5. ???????(HTTPS):????????SSL/TLS??,????????????????????????????????????

6. ?????HTTP?:?????HTTP?,?Content-Security-Policy?X-Content-Type-Options?X-Frame-Options,??????????

??,???????????????????PHP????????,??????URL???????