[RESOLVED]how to pass user info to diffrent pages using sessions?

[tony007]

Hi all i wonder how i can pass user information such as login name to diffrent pages using sessions. My intention is that i want in diffrent pages the php pages automatically knows who is using the page and where user log name is necessary it is avaliable by just doing echo $username or using $username in queries.Furthermore, i want the sessions some how expire within 15 min or so.I be happy if an expert show me how i can create sessions and how to use it in php pages for above purpuse. Thanks

[visualAd]

Session variables are stored in the super global array $_SESSION. Before using this array you need to initialise the session with session_start(). Once you have done this, any variable you save into it will be avialable accross all the scripts on your site.

session_start();

// to set the variable
$_SESSION['username'] =  $_POST['username'];

// to retrieve the variable
$username = $_SESSION['username']; 

To expire a session you could use the session.gc_maxlifetime conffig option. This will cause PHP to see the session as stale after a certain time and delete it. However, garbage cleanup is not performed on every script execution so it cannot be considered accutrate.

ini_set('session.gc_maxlifetime', '900'); // causes sessions to become stale after 15min 

The best way to do it is to use an additional variable called expire time. Each time the user makes a request to one of your scripts, set it too the current time and at the beginning of each script check to ensure the time elapsed from the previous request is not greater than 15 mins.

    session_start();

    if (isset($_SESSION['request_time'])) {
        if (time() - ((int) $_SESSION['request_time']) > 900) {
            // session expired
        }
    }

    $_SESSION['request_time'] = time(); 

If you check the link in my signature, I have a session class, which allows for easier management of sessions and for storage of session data in a MySql database.

[tony007]

visualAd many thanks for u helpfull post. I have a few questions :

1) do i need to use session_start(); in every page inside the directory that
i want to use seession?

2) if i define a variable inside sesssion where that php file containing session_start() is in one directory . Do u think that variable will be availabe in php pages inside other
folders?

3) where i want to utilize session variable do i need
to do :
$username = $_SESSION['username'];
echo $username

or do i have to add any other code before these 2 lines such
as using session_start()


4) May i know why u used $_POST['username']; is that
the way to recive form posted value and put it equal to session variable ?

// to set the variable
$_SESSION['username'] = $_POST['username'];


5) do i need to put session life time code after session start in every page ?

session_start();
ini_set('session.gc_maxlifetime', '900'); // causes sessions to become stale after 15min

6)
do i need to post this line in every page that i want use the stored variable in session ? or just once when i
login in to protectd folder ?session_start();

if (isset($_SESSION['request_time'])) { 
        if (time() - ((int) $_SESSION['request_time']) > 900) { 
            // session expired 
        } 
    } 

    $_SESSION['request_time'] = time();

[visualAd]

1) do i need to use session_start(); in every page inside the directory that i want to use seession?

Yes

2) if i define a variable inside sesssion where that php file containing session_start() is in one directory . Do u think that variable will be availabe in php pages inside other folders?

Yes, you can limit where the session cookie wil be seen by modifying the session.cookie_path setting.

3) where i want to utilize session variable do i need
to do :
$username = $_SESSION['username'];
echo $username

or do i have to add any other code before these 2 lines such
as using session_start()

You need to use session_start() first. If you do not, then using $_SESSION will simply generate an undefined variable notice.

4) May i know why u used $_POST['username']; is that
the way to recive form posted value and put it equal to session variable ?

// to set the variable
$_SESSION['username'] = $_POST['username'];

It was an example. Variables inside the $_POST array come from forms submitted via the post method. $_GET contains variables from the query string. You can assign any variable to the $_SESSION array.

5) do i need to put session life time code after session start in every page ?

session_start();
ini_set('session.gc_maxlifetime', '900'); // causes sessions to become stale after 15min

Yes, you need to call session_start() before you do anything with $_SESSION

6) do i need to post this line in every page that i want use the stored variable in session ? or just once when i
login in to protectd folder ?session_start();

if (isset($_SESSION['request_time'])) { 
        if (time() - ((int) $_SESSION['request_time']) > 900) { 
            // session expired 
        } 
    } 

    $_SESSION['request_time'] = time();

If you want your session to expire properly, then yes.

[jcavard]

dang visualad... that is one oe the best reply I seen, so detailed....

I dare you to do the same with this thread now