Timeout Session When There's No Activity From the User - php

Question

how can I timeout a session when there is no activity from the user?
Here is my code which has the name session.php:
<?php
require_once('conn.php');
session_start();
$user_check = $_SESSION['login_user'];
$ses_sql = mysqli_query($conn, "select * from employee where Username = '$user_check'");
$row = mysqli_fetch_array($ses_sql, MYSQLI_ASSOC);
$login_session = $row['EmployeeName'];
if (!isset($_SESSION['login_user'])) {
header("location:index.php");
}
?>

Answer 1

Include this code into the profile page you want to redirect to after logged in. First calculate the time like this.
<script>
var sec = 0;
var min = 0;
var hrs = 0;
function time () {
if (sec<=59) {
sec++;
if (sec<10) {
sec="0"+sec;
}
if (sec>59) {
sec=0;
min++;
if (min>59) {
min=0;
hrs++;
if (hrs>24) {
hrs=0;
};
};
};
};
document.getElementById("time").innerHTML=hrs+":"+min+":"+sec;
}
function tick () {
if (min<10) {
min="0"+min;
}
if (hrs<10) {
hrs="0"+hrs;
}
}
window.onload=function () {
tick();
setInterval(time,1000);
}
</script>
This will give you a time. After that do this. Let's assume you want to time it out in 30 seconds. Here login.php is any common page which redirects after logout.
<script>
if(sec == 30){
</script>
<?php
$_SESSION["login_user"] = NULL;
redirect_to("login.php");
?>
<script>
}
</script>
I hope this would work.