Drupal 8: Working with links in different ways.

drupal_8_working_with_links_in_different_ways.txt

// 1- Basic.
$url1 = Url::fromUri('https:www.google.com');
$link1 = Link::fromTextAndUrl('This is my link to Google', $url1);

// 2- Using classes URL and Link.
use Drupal\Core\Url;
use Drupal\Core\Link;

     // 2.1- Link to your Drupal Site Home page (declared in the file 'system.routing.yml').
     $url1 = Url::fromRoute('<front>');
     $link1 = Link::fromTextAndUrl('This is my First link to Home Page', $url1);

     //2.2- Link to /admin/people (declared in the file 'user.routing.yml').
     $url2 = Url::fromRoute('entity.user.collection');
     $link2 = Link::fromTextAndUrl('Link to the user admin page', $url2);

     //2.3- External Link to Drupal.org.
     $url3 = Url::fromUri('https://www.drupal.org');
     $link3 = Link::fromTextAndUrl('External link to Drupal.org', $url3);

     //2.4- Link to /admin/structure/blocks created with text and Url.
     $url4 = Url::fromRoute('block.admin_display');
     $link4 = Link::fromTextAndUrl(t('Block administration page'), $url4);

     //2.5- Link to the node with id = 1.
     $url5 = Url::fromRoute('entity.node.canonical', ['node' => 1]);
     $link5 = Link::fromTextAndUrl(t('Go to node with id = 1'), $url5);

     //2.6- Link to the edit mode of the node with id = 1.
     $url6 = Url::fromRoute('entity.node.edit_form', ['node' => 1]);
     $link6 = Link::fromTextAndUrl(t('Go to the edit mode'), $url6);
   
     //2.7- External Link to Gitlab with attributes.
     $url7 = Url::fromUri('https://gitlab.com');
     
     // We'll add some HTML attributes to the link. 
     $link_options = [
       'attributes' => [
         'target' => '_blank',
         'title' => 'Link to Gitlab web site',
       ],
     ];
     $url7->setOptions($link_options);
     $link7 = Link::fromTextAndUrl(t('Go to Gitlab web site'), $url7);

// 3- Using services with static methods from the \Drupal global class. 
    $url8 = Url::fromRoute('your_custom_module.what_a_great_route');
    $link8 = \Drupal::service('link_generator')->generate('My link created by static calling to service', $url8);


// 4- Using services in a dynamic way, passed as arguments to a constructor.

<?php

/**
 * @file
 * Contains \Drupal\your_custom_module\Controller\YourCustomController.
 */

namespace Drupal\your_custom_module\Controller;

use Drupal\Core\Utility\LinkGeneratorInterface;


class YourCustomController extends ControllerBase {
 protected $link_generator;

public function __construct(LinkGeneratorInterface $linkGenerator) {
    $this->link_generator = $linkGenerator;
  }

public static function create(ContainerInterface $container) {
    return new static(
      $container->get('link_generator')
    );
  }

public function link() {
// Add a link created dynamically with the 'link_generator' service.
    $url9 = Url::fromUri('https://twitter.com');
    $link9 = $this->link_generator->generate('Link to twitter', $url9);

    // Build the render output.
    $output['your_custom_module_links'] = [
      '#theme' => 'item_list',
      '#items' => $link9,
      '#title' => $this->t('Just a link generated with injected service: '),
    ];
    return $output;
  }
}