symfony 4 : How to get “/public” from RootDir

问题:

I have an image under the public folder.
How can I get my image directory in symfony4 ?
In symfony 3, it's equivalent is :

$webPath = $this->get('kernel')->getRootDir() . '/../web/';

回答1:

You can use either

$webPath = $this->get('kernel')->getProjectDir() . '/public/'; 

Or the parameter %kernel.project_dir%

$container->getParameter('kernel.project_dir') . '/public/';

回答2:

It is a bad practice to inject the whole container, just to access parameters, if you are not in a controller. Just auto wire the ParameterBagInterface like this,

protected $parameterBag;

public function __construct(ParameterBagInterface $parameterBag)
{
    $this->parameterBag = $parameterBag;

}

and then access your parameter like this (in this case the project directory),

$this->parameterBag->get('kernel.project_dir');

Hope someone will find this helpful.

Cheers.

回答3:

parameters:
    webDir: '%env(DOCUMENT_ROOT)%'

回答4:

In Controller (also with inheriting AbstractController):

$projectDir = $this->getParameter('kernel.project_dir');

回答5:

You can inject KernelInterface to the service or whatever and then get the project directory with $kernel->getProjectDir():

<?php

namespace App\Service;

use Symfony\Component\HttpKernel\KernelInterface;

class Foo
{
    protected $projectDir;

    public function __construct(KernelInterface $kernel)
    {
        $this->projectDir = $kernel->getProjectDir();
    }

    public function showProjectDir()
    {
        echo "This is the project directory: " . $this->projectDir;
    }
}