PHP会话（登录页面和用户页面）

Question

I need to create a session on index page if user already login in, it will header to member page. if user destroy session, it will stay at index(login page)

what i did is

if(session_start){
    header("location:member.php") or die();
}

if(isset($_POST['email']) && isset($_POST['password'])){



$email=strtolower($_POST['email']);
    $password=md5($_POST['password']);



if($email && $password){
        $connect=mysql_connect("localhost", "root", "");
        $database=mysql_select_db("phplogin", $connect);



$SQL=mysql_query("SELECT * FROM users WHERE email='$email'");
        $numrows=mysql_num_rows($SQL);



if($numrows!=0){
            while($result=mysql_fetch_assoc($SQL)){
                $db_email=$result['email'];
                $db_password=$result['password'];
                $db_firstname=$result['firstname'];
                $db_lastname=$result['lastname'];
                }
            }
        else{
            die("Can't find the user");
            }



if($email==$db_email && $password==$db_password){
            session_start();
            $_SESSION['firstname']=$db_firstname;
            $_SESSION['lastname']=$db_lastname;
            header("location:member.php");
            }   
        else{   
            die("wrong username or password");
            }
        }
    else{die("Please enter email or password");}
    }

This works when user haven't destroy session, but when user destroy session it didn't stay at index page

I need something like facebook, yet I don't know how facebook can share same the domain name on login page and user page.

so everytime i type facebook.com i will go to my user page, if i logout, it will become login page

Answer 1

You have used if(session_start). session_start() is a function. And it is used on each and every page. So it will redirect you everytime.

Another thing, you need to session_start() on the page you are storing the session and the page you are getting session values.

Instead of:

if(session_start){
    header("location:member.php") or die();
}  

Use:

session_start();
if(isset($_SESSION['firstname']) && isset($_SESSION['lastname'])){
    header('location:member.php');
}
//and REMOVE session_start(); from where you have written.