PHP / Ajax : How to show/hide DIV on $_SESSION variable value?

Question

I have searched many, many topics on the Net discussing about session variables and how to get them from Javacript through Ajax. However, though I have been able to do so, this

Answer 1

It's an idea, but you can work on/from it;

actionURL is a php file where you can check if the user is logged in with a valid session.

ajaxSession function returns true or false if the user is logged.

Then you can call this function every X seconds/minutes to control if the session still going.

window.setInterval(function(){
  // call your function here
  if(ajaxSession(actionUrl)){
      //return true, user logged, append/show protected divs.

  }else{
      //return false, remove/hide protected divs and ask user to log.

  }    
}, 5000); //every 5 seconds.

ajaxSession function:

 function ajaxSession(actionUrl) {
        var sessionOK= false;

        $.ajax({
        async: false,
        url: actionUrl,
        success: function(msg) {
             // check the return call from the php file.
              if(msg== 'OK'){ 
                 sessionOK = true;
              }else{
                 sessionOk = false;
              }
        }});

        return sessionOK;
    }

EDIT

I will add an example code for the actionUrl, that will return if the session is isset or not to the ajaxSession function:

<?php
    session_start();

    // $_SESSION['reg'] is true when the user is logged in.
    if($_SESSION['reg'] == true){
        echo 'OK';
    }else{
        echo 'NO';
    }
?>

Remember to check in the ajaxSession function the result of the Ajax call. If it's Ok, then sessionOk = true, if not, sessionOk = false.