How do I make index.php will control anything in PHP - php

Question

Firstly, I don't know what to call this thing :) I want to know the key, structure and example how to achieve my goal.
Example, I don't want create separate file like register.php, login.php, about.php faq.php. Here I want the register, login about, faq ,etc will handle by index.php by example, maybe something like index.php?p=register
How do I create page something like that and what this structure called in PHP programming. Let me know.

Answer 1

In index.php?p=register the part after ? is called "Query String". PHP will by default parse it for you and provides the superglobal $_GET. Just try it out yourself
var_dump($_GET);

Answer 2

To provide a more appropriate answer using Neals code, use basename to filter out non-essential file information:
$page = isset($_GET['p'])?basename($_GET['p']):'main';
include_once "$page.php";
You could also create a "white list" to ensure that only the proper files get included:
$whiteList = array('faq', 'register', 'profile');
$page = (isset($_GET['p']) && in_array($_GET['p'], $whiteList))?basename($_GET['p']):'main';
include_once "$page.php";
Both ways should be secure, obviously, the white list will be a bit more so. This tact, depending on how you do is generally referred to as "BootStrapping" IE, one entrance page to access the rest.
UPDATE
To further the security, I would set a variable, $included would be sufficient, to add to the pages that are being included. This would prevent direct access to them (assuming that register_globals is turned off like it should be, so something like:
$whiteList = array('faq', 'register', 'profile');
$page = (isset($_GET['p']) && in_array($_GET['p'], $whiteList))?basename($_GET['p']):'main';
$included = true;
include_once "$page.php";
Then on $page.php at the top you would have something like:
<?php
if (!$included)
die('Accessing the file directly is not allowed.');
Which would prevent calls to http://yoursite.com/register.php from being allowed to dish out the file. This has it's negatives to it. Instead of putting the files you are going to be including in the webroot, I would put them outside of the webroot or in an .htaccess protected directory, which would ensure that users could not access them directly and must access them through the index.php.

Answer 3

I'm not sure what the whole thing is called, but if you're using index.php like that, it's called a FrontController. It's how MVC frameworks work:
/index.php?q=ctrl/action
/index.php/ctrl/action
/ctrl/action
They're all handled by/in index.php using "ctrl/action"

Answer 4

You want to look up php templates or even html iframe. There are several ways to do this, but some are better than others. In asp.net it's called a MasterPage. Hopefully some of these terms help you out.

Answer 5

If you really want to do something like this, then you can use the get field, but you need to predefine your pages, so for this request: index.php?p=my_page
<?php
$page = $_GET['p'];
$pages = array(
'my_page' => 'mypage.php',
'another_page' => 'another.php',
...
);
$include = $pages[$page];
if(!empty($include)) {
include_once($include);
} else {
echo 'No such page';
}
?>
This keeps the include completely separate from what is passed on the URL so there is no chance for risky things to get passed.