PHP Session variable not passing - php

Question

I need to pass a variable which called 'square' between my php files, and everything is ok until I go to the action file to retrieve data from my database:
//plan.php
<?php
include("config.php");
session_start();
$loggeduser = $_SESSION['user'];
if (!isset($_SESSION['user']))
{
header("Location: login.php");
}
// Get selected square
$selsquare = $_GET["square"];
?>
<script>
$(document).ready(function(){
fetchUser();
function fetchUser()
{
var action = "Load";
$.ajax({
url : "action.php?square=$selsquare",
method:"POST",
data:{action:action},
success:function(data){
$('#result').html(data);
}
});
}
</script>
and here is my action.php file
<?php
//Database connection by using PHP PDO
$username = 'root';
$password = '';
$connection = new PDO( 'mysql:host=localhost;dbname=db', $username, $password );
$selsquare = $_GET["square"];
if(isset($_POST["action"]))
{
if($_POST["action"] == "Load")
{
$statement = $connection->prepare("SELECT * FROM plans WHERE square = '$selsquare' ");
$statement->execute();
$result = $statement->fetchAll();
$output = '';
$output .= '
<table class="table table-bordered">
<tr>
<th width="10%">ID</th>
<th width="10%">Square</th>
<th width="40%">Plan</th>
<th width="10%">Update</th>
<th width="10%">Delete</th>
</tr>
';
if($statement->rowCount() > 0)
{
foreach($result as $row)
{
$output .= '
<tr>
<td>'.$row["id"].'</td>
<td>'.$row["square"].'</td>
<td>'.$row["plan"].'</td>
<td><button type="button" id="'.$row["id"].'" class="btn btn-warning btn-xs update">Update</button></td>
<td><button type="button" id="'.$row["id"].'" class="btn btn-danger btn-xs delete">Delete</button></td>
</tr>
';
}
}
else
{
$output .= '
<tr>
<td align="center">Data not Found</td>
</tr>
';
}
$output .= '</table>';
echo $output;
}
?>
I need to retrieve all the data that has square = $selsquare but it is not working. The selsquare is working in the plan.php but not in action.php
Please help me figure out whats wrong

Answer 1

You are not doing it correctly. In your ajax method your method of passing data is post and in your action.php file you are fetching it as a get variable.
<script>
$(document).ready(function(){
fetchUser();
function fetchUser()
{
var action = "Load";
var square = "<?php echo $selsquare ?>";
$.ajax({
url : "action.php",
method:"POST",
data:{action:action, square:square},
success:function(data){
$('#result').html(data);
}
});
}
</script>
Now fetch square as post variable in action.php file
I haven't tested the code but it should work.

Answer 2

By default, PHP sessions require a cookie to identify them. You’re trying to run 2 separate PHP scripts (including the script for the Ajax call), so each will need access to the cookie.
Ajax by default doesn’t send cookies. This is a relatively new feature, but is supported in all current browsers.
First, you need to set the property withCredentials to true. This will allow the passing of cookies.
See http://api.jquery.com/jQuery.ajax/
$.ajax({
url: a_cross_domain_url,
xhrFields: {
withCredentials: true
}
});
In PHP, you will also need to include a statement like:
header("Access-Control-Allow-Credentials: true");
in your responding script.
Alternatively, you can instruct PHP to accept the session id and get Ajax to send it as a query string.

Answer 3

You are sending POST from Javascript, while in your PHP you are reading as $_GET.
<script>
$(document).ready(function(){
fetchUser();
function fetchUser()
{
var square_js = '<?php echo $selsquare; ?> ';
$.ajax({
url : "action.php?square=$selsquare",
method:"GET",
data:{square:square_js},
success:function(data){
$('#result').html(data);
}
});
}
</script>
If your square has the value ABCDEF, then in your PHP, you will get the request this way
print_r($_GET);
Array{
"square" => "ABCDEF"
}
Recommended way of passing string in double quote is with {}
url : "action.php?square=$selsquare",
Should be
url : "action.php?square={$selsquare}",