How to use your service in Symfony 2 php template engine?

Question

symfony

$foo = $this->get('foo');
This code works in the controller. However, if used in a php template engine, it gives

The helper "foo" is not defined.

The following is written in services.yml:
services: foo: class: App\CoreBundle\Classes\Foo
Thanks in advance…

Answer 1

so get your service in controller and pass it to template

Answer 2

Need to use Twig Globals