--- /dev/null
+<?php
+
+namespace Drupal\{{ machine_name }}\Plugin\Block;
+
+use Drupal\Core\Access\AccessResult;
+use Drupal\Core\Block\BlockBase;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\Core\Routing\RouteMatchInterface;
+use Drupal\Core\Session\AccountInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Provides a '{{ plugin_label }}' block.
+ *
+ * @Block(
+ * id = "{{ plugin_id }}",
+ * admin_label = @Translation("{{ plugin_label }}"),
+ * category = @Translation("{{ category }}")
+ * )
+ */
+class {{ class }} extends BlockBase implements ContainerFactoryPluginInterface {
+
+ /**
+ * The route match.
+ *
+ * @var \Drupal\Core\Routing\RouteMatchInterface
+ */
+ protected $routeMatch;
+
+ /**
+ * Constructs a new {{ class }} instance.
+ *
+ * @param array $configuration
+ * The plugin configuration, i.e. an array with configuration values keyed
+ * by configuration option name. The special key 'context' may be used to
+ * initialize the defined contexts by setting it to an array of context
+ * values keyed by context names.
+ * @param string $plugin_id
+ * The plugin_id for the plugin instance.
+ * @param mixed $plugin_definition
+ * The plugin implementation definition.
+ * @param \Drupal\Core\Routing\RouteMatchInterface $route_match
+ * The route match.
+ */
+ public function __construct(array $configuration, $plugin_id, $plugin_definition, RouteMatchInterface $route_match) {
+ parent::__construct($configuration, $plugin_id, $plugin_definition);
+ $this->routeMatch = $route_match;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+ return new static(
+ $configuration,
+ $plugin_id,
+ $plugin_definition,
+ $container->get('current_route_match')
+ );
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function defaultConfiguration() {
+ return [
+ 'content' => $this->t('Hello world!'),
+ ];
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function blockForm($form, FormStateInterface $form_state) {
+ $form['content'] = [
+ '#type' => 'textarea',
+ '#title' => $this->t('Block content'),
+ '#default_value' => $this->configuration['content'],
+ ];
+ return $form;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function blockSubmit($form, FormStateInterface $form_state) {
+ $this->configuration['content'] = $form_state->getValue('content');
+ }
+
+ /**
+ * {@inheritdoc}
+ *
+ * @DCG Remove this method of you do not need any access restrictions.
+ */
+ protected function blockAccess(AccountInterface $account) {
+ $route_name = $this->routeMatch->getRouteName();
+ // Display the block only for anonymous users.
+ if ($account->isAnonymous() && $route_name != 'user.register') {
+ return AccessResult::allowed()
+ ->addCacheContexts(['route.name', 'user.roles:anonymous']);
+ }
+ return AccessResult::forbidden();
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function build() {
+ $build['content'] = [
+ '#markup' => $this->configuration['content'],
+ ];
+ return $build;
+ }
+
+}