Retrieve current users id from database to use in new tabel - php

Question

I have a profile page where I retrieve users information.
Profile.php
<?php
require 'core/init.php';
if(!$username = Input::get('user')) {
Redirect::to('index.php');
} else {
$user = new User($username);
if(!$user->exists()) {
Redirect::to(404);
} else {
$data = $user->data();
}
?>
<h3><?php echo escape($data->username); ?></h3>
<p>Membership No: <?php echo escape($data->id); ?></p>
<p>Full name: <?php echo escape($data->name); ?></p>
<p>Date of birth: <?php echo escape($data->dob); ?></p>
<p>Location: <?php echo escape($data->location); ?></p>
<p>Join date: <?php echo escape($data->joined); ?></p>
<?php
I want to retrieve the id of my user to insert into another table in my order page, so far I have this
oerder.php
<?php
session_start();
require 'core/init.php';
$Band_id = mysql_real_escape_string($_POST['band']);
$user_id = $_SESSION['id'];
$sql = "INSERT INTO orders (band_id,user_id) VALUES('$Band_id', '$user_id')";
mysql_query ($sql, $linkme)
or die ("could not add to database");
?>
currently $user_id = $_SESSION['id']; is not placing the users id in my table orders.
I tried
<?php echo escape($data->id); ?>
and
$user_id = $_GET['id'];
but it dose not work, dose anyone know how to retrieve the users id so I can insert it into the db?

Answer 1

What you could do is save user data to the session
$_SESSION['user_data'] = $user->data();
you could assign it back to $data once you check $_SESSION['user_data'] is set, else re query the model.
And session_start() should also be at the top of every file you want to hold session for.
So something like:
Profile.php
<?php
session_start();
require 'core/init.php';
if(!$username = Input::get('user')) {
Redirect::to('index.php');
exit;
}
if(!isset($_SESSION['user_data'])){
$user = new User($username);
if(!$user->exists()) {
Redirect::to(404);
exit;
}
$_SESSION['user_data'] = $user->data();
}
?>
<h3><?php echo escape($_SESSION['user_data']->username); ?></h3>
<p>Membership No: <?php echo escape($_SESSION['user_data']->id); ?></p>
<p>Full name: <?php echo escape($_SESSION['user_data']->name); ?></p>
<p>Date of birth: <?php echo escape($_SESSION['user_data']->dob); ?></p>
<p>Location: <?php echo escape($_SESSION['user_data']->location); ?></p>
<p>Join date: <?php echo escape($_SESSION['user_data']->joined); ?></p>
oerder.php
<?php
session_start();
require 'core/init.php';
if(!isset($_SESSION['user_data'])){
Redirect::to('index.php');
exit;
}
$Band_id = mysql_real_escape_string($_POST['band']);
$user_id = $_SESSION['user_data']->id;
$sql = "INSERT INTO orders (band_id,user_id) VALUES('$Band_id', '$user_id')";
mysql_query ($sql, $linkme)
or die ("could not add to database");
?>
also you should move over to PDO or mysqli.