Question

I am getting started with Symfony 2 & I am following this tutorial. Now, this tutorial is easy & I was able to follow it completely. This is the code in my Controller

<?php
namespace DemoCompany\HelloBundle\Controller;

use Symfony\Component\HttpFoundation\Response;

class HelloController{
    public function indexAction($name){
        return new Response('<h1>hello ' . ucfirst($name) . '</h1>');
    }
}

Now, I have some questions

1. When I run the code without including namespace DemoCompany\HelloBundle\Controller;, it gives me an error. But it does work fine when this line is included; so I want to know: Why does it work with namespace statement & why doesn’t it work without namespace. Please clarify.

2. Follow up question: I am returning a new Response object but it is neither being defined, nor is my class HelloController extending some baseclass (which may have this response object defined). So the question is: How is PHP able to find & then load this file?

3. In Symfony, do custom controllers/models/views need to extend some base class? For example, in Codeigniter, we have to do something like class Blog extends CI_Controller, so that all the methods defined in CI_Controller would be available in current scope using $this. Does Symfony have the same practice or does it do something different?

4. Since this controller is namespaced to DemoCompany\HelloBundle\Controller, how come normal PHP functions work without a backslash?

Answer 1

I’ve only very briefly used Symfony2, here are my answers though:

1) That’ll be because Symfony needs your Controller to exist in the DemoCompany\HelloBundle\Controller namespace for autoloading

2) At use Symfony\Component\HttpFoundation\Response;, you’re telling PHP to look in there if the method can’t be found locally

3) Don’t know on that one…

4) Built-in PHP functions aren’t in any specific namespace (namespaces are new to PHP), so work anywhere