Defining session start in if block causing the session to create again on page refresh

Question

if(!isset($_SESSION['SessData'])) {
    session_name('sess1');
    session_start();

    echo '----- In IF Condition -----';
    print_r($_SESSION['SessData']['Tracker']['Source']);
}
else {
    echo '----- In ELSE Condition -----';
    print_r($_SESSION['SessData']['Tracker']['Source']);
}

When executing the code its only going in the IF condition and not the else condition. Whats the reason behind it?

But what's the reason behind that? First time in IF condition the session will be created so next time on page refresh it should come in else statement. Isn't it? Correct me on this if I'm wrong... — Mohammad Sharaf Ali, Jan 31 '16 at 17:49
Check this link:-http://www.thecreativedev.com/session-start-at-the-top-of-the-page/ — Alive to die - Anant, Jan 31 '16 at 17:52
Read the link but it states no print or echo statements before session_start or setcookie and in my code the echo statement is after session_start. — Mohammad Sharaf Ali, Jan 31 '16 at 17:57
You can't print a session value without a started session. It makes the else part redundant. Unless you are starting the session somewhere else previously. — Progrock, Jan 31 '16 at 18:00
@Progrock Okay assume 1st time the if condition becomes true and the session starts. Then I refresh my page and since the session is not already started so it will come in else part. Right? — Mohammad Sharaf Ali, Jan 31 '16 at 18:02
Why don't you understand that you can not apply anything (conditions, assignment, iteration etc)on session variables till you not started session in beginning. So your code will give some undefined index type error always — Alive to die - Anant, Jan 31 '16 at 18:04
When you refresh your page you will be back to square one. Whenever you need to refer to a session, you have to use session_start(). — Progrock, Jan 31 '16 at 18:04
@Progrock if I put it at the top of the page and refresh page every time will result in the session_start() statement being executed everytime. — Mohammad Sharaf Ali, Jan 31 '16 at 18:06
yes and then only you can apply anything on session, session variables and values are not accessible till you are not starting session — Alive to die - Anant, Jan 31 '16 at 18:09
@A-2-A see this http://stackoverflow.com/questions/13114185/how-can-you-check-if-a-php-session-exists — Mohammad Sharaf Ali, Jan 31 '16 at 18:12
@A-2-A the solution in the above link is checking the session in the same way as I. — Mohammad Sharaf Ali, Jan 31 '16 at 18:13
http://stackoverflow.com/questions/6249707/check-if-php-session-has-already-started check the link, but the solution here depends upon your PHP version.. — ameenulla0007, Jan 31 '16 at 18:15
You are checking session data and either it have some value or not you can not access it till you not start the session. starting the session will not affect session variables an there values — Alive to die - Anant, Jan 31 '16 at 18:17

score 0 · Answer 1 · answered Jan 31 '16 at 18:28

The working code is as follows:

if(phpversion()  < '5.4.0') {
    if(session_id() == '') {
        session_name('sess1');
        session_start();
        echo 'here1';
    }
    else {}
}
else if(phpversion()  >= '5.4.0') {
    if(session_status() == PHP_SESSION_NONE) {
        session_name('sess1');
        session_start();
        echo 'here2';
    }
    else {}
}


if(!isset($_SESSION['SessData'])) {
    echo '----- In IF Condition -----';
    print_r($_SESSION['SessData']['Tracker']['Source']);
    echo '<br />';
    echo session_id();
}
else {
    echo '----- In ELSE Condition -----';
    print_r($_SESSION['SessData']['Tracker']['Source']);
    echo '<br />';
    echo session_id();
}

Defining session start in if block causing the session to create again on page refresh

1 Answers1