Check if PHP session has already started

Question

I have a PHP file that is sometimes called from a page that has started a session and sometimes from a page that doesn\'t have session started. Therefore when I have s

Answer 1

if (version_compare(PHP_VERSION, "5.4.0") >= 0) {
    $sess = session_status();
    if ($sess == PHP_SESSION_NONE) {
        session_start();
    }
} else {
    if (!$_SESSION) {
        session_start();
    }
}

Actually, it is now too late to explain it here anyway as its been solved. This was a .inc file of one of my projects where you configure a menu for a restaurant by selecting a dish and remove/add or change the order. The server I was working at did not had the actual version so I made it more flexible. It's up to the authors wish to use and try it out.

Answer 2

You can use the following solution to check if a PHP session has already started:

if(session_id()== '')
{
   echo"Session isn't Start";
}
else
{
    echo"Session Started";
}

Answer 3

This is what I use to determine if a session has started. By using empty and isset as follows:

if (empty($_SESSION)  && !isset($_SESSION))  {
    session_start();
}

Answer 4

Use session_id(), it returns an empty string if not set. It's more reliable than checking the $_COOKIE.

if (strlen(session_id()) < 1) {
    session_start();
}

Answer 5

On PHP 5.3 this works for me:

if(!strlen(session_id())){
    session_name('someSpecialName');
    session_start();
} 

then you have. If you do not put the not at if statement beginning the session will start any way I do not why.

Answer 6

if (session_id() === "") { session_start(); }

hope it helps !