CodeIgniter URI Routing Routes Learn with Example

What are Routes?

Routes are responsible for responding to URL requests. Routing matches url to predefined routes

URI Routing

URL string and its corresponding controller class/method. The segments in a URI normally follow this pattern:

example.com/class/function/id/

Setting your own routing rules

See the controller first then will will set our routes

application/controllers/Catalog.php 

<?php

defined('BASEPATH') OR exit('No direct script access allowed');

class Catalog extends CI_Controller {

    public function __construct() {
        parent::__construct();
    }

    public function index() {
        //code will be here 
    }

    public function product_with_one_param($id) {
        //code will be here 
    }

    public function product_with_two_param($id, $title) {
        //code will be here 
    }

}

Lets now understand routing rules are defined in your application/config/routes.php file.

<?php
//Catalog is the Controller name have index method
$route['journals'] = 'Catalog';// you can access like this http://ci_project/journals

// (:any) will match a segment containing any character
$route['product/(:any)'] = 'catalog/product_with_one_param/$1';

//(:num) will match a segment containing only numbers
$route['product/(:any)/(:any)'] = 'catalog/product_with_two_param/$1/$2'; // you can increase as you want $1 $2 $3....
?>

• (:any) will match a segment containing any character
• (:num) will match a segment containing only numbers

Reserved Routes

There are three reserved routes:

//Default Controller Create your own controller and you can replace welcome to ...
$route['default_controller'] = 'welcome';

// page not found you can define your own controller & custom 404 page
$route['404_override'] = ''; 

//allow uri_dashes
$route['translate_uri_dashes'] = FALSE;