Question

I’m logging in a user with a jQuery $.post AJAX request and in the ajax.php im setting the $_SESSION[‘login’] variable (the session_start() was called in index.php) along with other login stuff, however when I try reference the $_SESSION[‘login’] variable on other pages then it is not set…

this is my POST code

    $.post('/assets/ajax/ajaxLogin.php',{username: $('[name=username]').val()
    ,password: $('[name=password]').val()},function(data){

    if(data.success)
    {
      location.href=data.redirect;     
    }
    else
    {
      $('#errorConsole').html(data.message).slideDown();
    }

    },'json');

and in ajaxLogin.php i am setting $_SESSION[‘login’]=”1″. So ajax script logs the user in if they have the right info, but when they are redirected to dashboard.php, I try to echo $_SESSION[‘login’] and I get an error,

Am I not setting the $_SESSION correctly, or will the ajax request not set variables globally??

this is the ajaxLogin.php

    <?php 

    if(!include('../../config.php')){
        echo 'include failure';
    }

    if($_POST){

        $myusername=$_POST['username']; 
        $mypassword=$_POST['password'];
        // To protect MySQL injection (more detail about MySQL injection)
        $myusername = stripslashes($myusername);
        $mypassword = stripslashes($mypassword);
        $myusername = mysql_real_escape_string($myusername);
        $mypassword = mysql_real_escape_string($mypassword);

        $sql="SELECT * FROM users WHERE username='$myusername' and                 password='$mypassword'";
        $result=mysql_query($sql);

        // Mysql_num_row is counting table row
        $count=mysql_num_rows($result);
        if($count==1)
        {
            $_SESSION['login'] = 1;
            $data['success'] = true;
            $data['redirect'] = '/dashboard.php';
        }
        else
        {
            $data['success'] = false;
            $data['message'] = "Your info is wrong....";
        }
        echo json_encode($data);
    }

    ?>

and also here is dashboard.php

    <?php 
        include('includes.php');
    ?>
    <?php
    if(!isLoggedIn())
    {
    echo 'You are not logged in';
    }
    else
    {
    echo 'You are logged in';  
    }
    ?>

and isLoggedIn() is:

    function isLoggedIn(){

        if (isset($_SESSION['login'])){
            return 1;
        }
        else
        {
            return 0;
        }
    }

Answer 1

You need to call session_start() on every page that uses sessions (and before you use them). This includes each file used in an AJAX request as well as the dashboard.php file.

Note: doesn’t apply to files included with include/require.