drupal 8，如何调试一个类？

Question

I want to train myself to use Drupal 8 (Im from drupal 7 =) ). So, I learned some symfony2 basics. Now, I would like know if there is a good way about the code debugging, I mean : Before with Drupal 7, I used the devel module for show the content of data (very usefull !). I try this module for drupal 8 but the dpm function seems not work in the class context.

Bu example, I use this code for alter some route :

<?php
namespace...
use...
...

class RouteSubscriber extends RouteSubscriberBase{
  public function alterRoutes(RouteCollection $collection){
    // What is the best way for display the $collection array ? like a dpm ? 
    dpm($collection); // doen't work, nothing appears in any page
  }

Thanks =)

Answer 1

Use debug() in Drupal 8. debug() will print the content of the variables as messages on the site. Alternatively, you can use a debugging tool like xdebug to examine your variables.

Answer 2

If you're used to using the Devel debug functions like dsm() and dpm() , you would feel right at home using Devel Kint . Just enable the module Devel Kint and use it in modules or theme with kint($variables) .

I would also look into using Xdebug and setting break points to debug at a deeper level.