CI 4 What are Parametrized Routes?

This is very common to every web application i.e Passing parameters to URLs. Also called as parameterized routing of application.

We will see about URL Placeholders & With Parameters in this section.

URL Placeholders

In CodeIgniter 4 application, there are several types of placeholder available to pass value to URL. Parameters as like of type Integer value, String value, Hashed value, Alpna numeric etc.

Let’s take an example to see How can we pass and access value to controller?

Open Routes.php file from /app/Config folder.

//...

$routes->get("my-route/(:num)", "MyController::myRoute/$1");
$routes->get("sample-route/(:any)/(:num)", "MyController::sampleRoute/$1/$2");

Here, we have configured few routes.

• First route will take a numeric value into URL as (:num) placeholder. We can pass any value there is no restriction with this placeholder i.e (:num) means only integer value. But I suggest, while developing any kind of application all things should be meaningful. That’s why use (:num) only when pass numeric value into URLs.
• $1 in first route – Passing url value to myRoute() method.
• Second route will take 2 values – one is any type means integer, string etc and other is for numeric value.
• $1 is for (:any) value and $2 is for numeric value. These two values $1 & $2 we are passing inside sampleRoute() method.

Example URLs

• /my-route/12
• /my-route/45 … etc
• /sample-route/hi/40
• /sample-route/256/120

Access URL values to Controller

<?php

namespace App\Controllers;

use App\Controllers\BaseController;

class MyController extends BaseController
{
	public function myRoute($id)
	{
		// .. code here
	}

	public function sampleRoute($key, $id)
	{
		// .. code here
	}
}

• myRoute($id) – Get (:num) value to method. This $id variable contains the URL value.
• sampleRoute($key, $id) – Get (:any) & (:num) value. These two variables contains the URL value.