为什么没有在此功能中设置登录和会话ID？

Question

I am try to loggin in and setting the session id.Below code did not authenticate the login successfully and did not set the session id.Plz help.

  public $userid;

  function login()
    {
        $pwdHasher = new PasswordHash(8, FALSE);

        if(isset($_POST['logging'])  AND  !empty($_POST['logging'])){


            $email=mysqli_real_escape_string($this->db->connection ,$_POST['email']);
            $pass=mysqli_real_escape_string($this->db->connection ,$_POST['pass']);
            $sql=mysqli_query($this->db->connection,"SELECT * FROM user where email='$email' AND password='$pass'");
            $numrows=mysqli_num_rows($sql);
            $resid=mysqli_fetch_array($sql);
            $checked = $pwdHasher->CheckPassword($pass,$numrows);
            if($checked){
                $this->userid=$_SESSION['id']=$resid['id'];

                $this->login=TRUE;


                echo "u r logedin.Plz click here to go  to main area<a href='main.php'>main</a>";
            }
            else{
                echo "username r password is wrong";
                $this->login=FALSE;
            }
        }
    }

Answer 1

You need to start a session with session_start() before using the $_SESSION array