Dynamic navigation using PHP include - php

Question

I have a question about how I can dynamically change the content to display in the webpages.
I have few portions of the website fixed - header, nav, footer, and splash and a side bar.
I only want the middle portion of my website to change based on the menu link what user clicks on.
Below is my code for index.php
<?php
include "/templates/header.php";
include "templates/menu.php";
include "/templates/splash.php";
$action = "index";
$disallowed_paths = array('header','menu','splash','bottom_page', 'footer');
if (!empty($_GET['action']))
{
$tmp_action = basename($_GET['action']);
if (!in_array($tmp_action, $disallowed_paths) && file_exists("/content/$tmp_action.php"))
$action = $tmp_action;
}
include "/content/$action.php";
include "/templates/bottom_page.php";
include "/templates/footer.php";
?>
My menu.php contains links for Home, About, products, services and login links
I just want to change the main_index.php to include the above based on what user clicks on.
please advise if this approach is good.
or should I create similar file as index.php multiple times with includes to each file as per the link clicked on menu

Answer 1

Your Answer is
GET method
You can use get method for that
<ul>
<li>example 1</li>
<li>example 2</li>
<li>example 3</li>
<li>example 4</li>
</ul>
After User Clicks on the link
<?php
if(isset($_GET['page']) && $_GET['page']!=""){
$page = "";
switch ($_GET['page']) {
case 'example_1':
$page = "Page_1.php";
break;
case 'example_2':
$page = "Page_2.php";
break;
case 'example_3':
$page = "Page_3.php";
break;
case 'example_4':
$page = "Page_4.php";
break;
default:
$page = "any_default_page.php";
break;
}
include($page);
}
?>
And there are other ways also. but this is the most easy and efficient

Answer 2

I think better approach would be whitelisting instead of blacklisting.
$existing_pages = array('home', 'contact', 'terms-of-service');
if(isset($_GET['action'] && in_array($_GET['action'], $existing_pages)
{
// load action here
} else {
//show 404 error
}
Note that your overall approach is not ideal, you could look like into modern frameworks like Laravel or Symphony which has templating systems which helps alot.
But for learning purposes this is fine:)