Serve multiple pages from 1 PHP file?

Question

So basically i am struggling with the need of optimizing my code for some project of mine. Currently i have pages like add_company.php, view_company.php

Answer 1

A very easy solution would be to just use includes.

if ($_GET["action"] == "view") {
  require("action_view.php");
} else if ...

(of course, you might want to use a switch statement, if you have lots of different page types)

Then action_view.php contains just the code for the specific page.

Better, but also more complicated solutions, would be an object oriented approach (abstract Page class with Factory Pattern) or forthright a good framework and template engine.