PHP標頭身份驗證奇怪的代碼

Question

我從PHP.net代碼復制以進行標頭驗證

這是代碼：

<?php
$valid_passwords = array ("Itay" => "1234", "beta" => "password");
$valid_users = array_keys($valid_passwords);
$user = $_SERVER['PHP_AUTH_USER'];
$pass = $_SERVER['PHP_AUTH_PW'];
$validated = (in_array($user, $valid_users)) && ($pass == $valid_passwords[$user]);
if (!$validated) {
  header('WWW-Authenticate: Basic realm="this is testing area. beta testers only!"');
  header('HTTP/1.0 401 Unauthorized');
  die ("Not authorized");
}
// If arrives here, is a valid user.
?>

現在，我的問題是為什么這行：

$validated = (in_array($user, $valid_users)) && ($pass == $valid_passwords[$user]);

用於代替

$validated = $pass == $valid_passwords[$user];

Answer 1

$validated = (in_array($user, $valid_users)) && ($pass == $valid_passwords[$user]);

該行檢查用戶是否存在以及密碼是否正確。

如果您取消用戶檢查，則用戶=“ nonexisting”和密碼=“”將有效（當然，會有通知。

校驗：

$pass = "";
$user = "any non existing"
$validated = ($pass == $valid_passwords[$user]); //here will be notice
var_dump($validated);