不在对象上下文中使用 $this [关闭]

Question

此代码在我的user.php 文件中

include('password.php');
class User extends Password{

        private $_db;

        function __construct($db){
            parent::__construct();

            $this->_db = $db;
        }

        private function get_user_hash($email){ 

            try {
                $stmt = $this->_db->prepare('SELECT password FROM users WHERE email = :email AND active="Yes" ');
                $stmt->execute(array('email' => $email));

                $row = $stmt->fetch();
                return $row['password'];

            } catch(PDOException $e) {
                echo '<p class="bg-danger">'.$e->getMessage().'</p>';
            }
        }

        public function login($email,$password){

            $hashed = $this->get_user_hash($email);

            if($this->password_verify($password,$hashed) == 1){

                $_SESSION['loggedin'] = true;
                return true;
            }   
        }

        public function logout(){
            session_destroy();
        }

        public function is_logged_in(){
            if(isset($_SESSION['loggedin']) && $_SESSION['loggedin'] == true){
                return true;
            }       
        }
    }

这段代码是我login.php 文件的一部分

function login($email,$password){

$hashed = $this->get_user_hash($email);  <--the error is in this line

if($this->password_verify($password,$hashed) == 1){

    $_SESSION['loggedin'] = true;
    return true;
}     

老实说，我不知道该怎么做，我还在学习这些东西，而且我对类和对象并不是很擅长，这就是为什么我要求大家帮助我解决这个问题。

Answer 1

替换这一行

$hashed = $this->get_user_hash($email);  <--the error is in this line

有

$user = new User($db);
$hashed = $user->get_user_hash($email);

你不能在课堂外使用它。您可以在下面的 SO 帖子中了解有关 $this 的更多信息。 What does the variable $this mean in PHP?