会话ID未设置但页面登录

Question

I am trying to write a login/session page for the first time in oop style. When I run the script below, the page redirects, but when i try to echo session id, it does nothing shows. Am I doing this the right way?

<?php
      session_start();
require_once('classes/function.php');
require_once('classes/user.php');

class Session{

    private $is_logged_in = FALSE;
    private $id ;
Public $ user_data;
    private $email ;

public function logout(){
    session_start();
    unset($_SESSION['id']);
    unset($this->id);
    session_destroy();
    $is_logged_in = FALSE;
    Misc::redirect('index.php');
}

public function is_logged_in(){
    return $this->is_logged_in ;
}

public function login($email, $password){
    global $user;
    global $misc;

    if($misc->check_form()){
        echo $this->error;
    }
    if (!MIsc::check_email_format($email)) {
            echo "Email format is invalid";
          }
          $login_user = $user->authenticate($email, $password);
          if($login_user){
            $_SESSION['id'] = $this->id = $this->user_data['id'];
            $_SESSION['email'] = $this->email = $this->user_data['email'];
            $is_logged_in = TRUE;
            Misc::redirect('127.0.0.1/users/index.php');
          }
}
}

$session = new Session;
?>

my login page looks like this

<?php
require_once('classes/user.php');
require_once('classes/session.php');
require_once('classes/function.php');

if(isset($_POST['submit'])){
    try{
    $email =$_POST['email'];
    $password = $_POST['password']; 
    $user = new Users;
     $user->authenticate($email , $password);
    $login = new session;
    $login->login($email , $password);
}
 catch (Exception $e){
    $error = new Errors();
    echo "<b>".$error->displayError($e)."</b>";
}
}

?>

$user_data is gotten from these methods

  public function user_exist($email){
  global $db;
  $stmt = $db->dbh->prepare("SELECT id, password, email FROM $this->table WHERE `email`= :email LIMIT 1");
  $stmt->bindValue(':email', $email);
  $stmt->execute();
  if($stmt->rowCount() == 1) {
     $this->user_data = $stmt->fetch();
     return TRUE;
  } else {
     throw new Exception('User do not exist');
  }
}

  /*
  what does this method do
*/
 public function authenticate($email, $password){
   global $db;
  $auth = $this->user_exist($email);
  if($auth) {
     if(password_verify($password, $this->user_data['password'])) {
       return  $this->user_data;
     } else {
        throw new Exception('Email/Password combination incorrect');
     }
  }
 }

Answer 1

Probably you are wrong in this section..

     $login_user = $user->authenticate($email, $password);
      if($login_user){
        $_SESSION['id'] = $this->id = $this->user_data['id'];
        $_SESSION['email'] = $this->email = $this->user_data['email'];
        $is_logged_in = TRUE;
        Misc::redirect('127.0.0.1/users/index.php');
      }

I can see that $user_data is not declared in class you should declare it before using it.

Another issue i see in your oop style

 public function authenticate($email, $password){
   global $db;//you should have $db declared in class, SInce it is not used here you should remove
  $auth = $this->user_exist($email); //Why you are assigning it to $auth you should directly place in condition if you need it once
  if($auth) {
     if(password_verify($password, $this->user_data['password'])) {  //You already have $password variable
       return  $this->user_data; //you can return true instead of returning object which you are not reusing.
     } else {
        throw new Exception('Email/Password combination incorrect'); //i like it :)
     }
  }

You should also enable error reporting to check the issue

ini_set('display_startup_errors',1);
ini_set('display_errors',1);
error_reporting(-1);