Rerouting in CodeIgniter is really simple if you already know how paths work in the framework. You have a controller that is used as the route redirect target. In other words, it picks up the redirected path as its own. Everything other than that is simple CodeIgniter coding. The path can be as many variables large as you may require.
Fairly complex routing systems can be set up this way without the bit of complexity you would have using straight php without a framework. Below is a short and sweet, step by step simple example of how to accomplish a two variable reroute.
Step By Step
First Step is download CodeIgniter from their website.
Second Step is to unzip it into your server root or a subfolder.
Third Step is to create a .htaccess file that tells apache how to handle requests. This step isn’t necessary if you don’t care about index.php being in your paths. My code is installed in a subfolder named ciredir on my Xampp server in Windows: