Unable to read GET variable when used in $page_content - php

Question

I have a file called productFocus.php where I use the GET variable ID: $id = $_GET["id"];
However this page is used in the product.php file in the following manner:
product.php
<?php
$page_content = 'productFocus.php'; // $id = $_GET["id"];
include('master.php');
?>
productFocus.php
<?php
include "db/db.php";
$id = $_GET["id"];
$product = get_product_by_id($id);
?>
<div class="product-focus">
<h3><?php echo $product->name ?></h3>
<img src="/images/products/<?php echo $product->image ?>">
<div id="description">
<h4>Productinformatie</h4>
<p><?php echo $product->description ?></p>
<h4>Partners</h4>
<table>
<?php
foreach($product->partners_obj as $partner) {
?>
<tr>
<td>
<a href=<?php echo $partner->$product_url ?> target="_blank">
<img id="partner" src="/images/partners/<?php echo $partner->image ?>">
</a>
</td>
<td>
<?php $partner->$product_price ?>
</td>
</tr>
<?php
}
?>
</table>
</div>
</div>
master.php
//HTML code
...
<?php include($page_content);?>
...
//HTML code
When I browse to productFocus.php?id=324324 I can read the GET variable, but when I browse to product.php?id=324324 I do not have access to the GET variable ID.
Is there an elegant way to solve this issue?

Answer 1

You need to check the GET variable before you call the product details in the prodcts.php file before regular page load.
<?php
if (isset($_GET['id'])) {
// GET PRODUCT DATA
}else{
// LOAD PRODUCTS PAGE
}
?>
As for getting the product details, I would suggest writing the separate call to the database, but if you just need to load page content, you are not calling it properly:
$id = $_GET['id'];
$fileurl = 'products.php?id='.$id;
$pagecontent = file_get_contents('$fileurl');