Magento 2 get admin url with key and parameters

Question

I don't understand why but in many topics I see that to get and admin route url with secure key and parameter I only need to use :

$this->urlBuilder->getUrl('adminhtml/myroutename/mycontroller/myaction', array('myparam' => 'myvalue'))

and urlBuilder I a Magento\Framework\UrlInterface object.

But in front, I get this URL: http://mysite.lan/adminhtml/myroutename/mycontroller/myparam/myvalue/

And if I remove the adminhtml I get this URL: http://mysite.lan/myroutename/mycontroller/myaction/myparam/myvalue/

So how can I create a correct admin URL with the key and the params?

Answer 1

If you are in an admin controller, you can just get the URL from the context (which is injected in the constructor):

$url = $this->context->getUrl();

$myUrl = $url->getUrl('adminhtml/myroutename/mycontroller/myaction', array('myparam' => 'myvalue'));

/This change with remove bracket/

Answer 2

There is a backend URL builder that backend controllers utilize.
Excerpt from abstract backend controller:

<?php

namespace Magento\Backend\App;

abstract class AbstractAction extends \Magento\Framework\App\Action\Action
{
    /**
     * @param \Magento\Backend\App\Action\Context $context
     */
    public function __construct(Action\Context $context)
    {
        parent::__construct($context);
        // ...
        $this->_backendUrl = $context->getBackendUrl();
        // ...
    }

// ...

You can access the URL builder from within any controller via $this->_backendUrl or inject it directly into a class:

<?php

use Magento\Backend\Model\UrlInterface;

class ExampleClass
{
    public function __construct(UrlInterface $backendUrl) {
        $this->backendUrl = $backendUrl;
    }
}

From there, you can build admin URL's like so:

$this->_backendUrl->getUrl(
    'myroutename/mycontroller/myaction',
    [
        'myparam1' => 'myvalue1',
        'myparam2' => 'myvalue2'
    ]
);