getEntityLabels example

$form['markup'] = [
        '#markup' => '<div class="js-form-item form-item">' . $this->t('An invalid vocabulary is selected. Please change it in the options.') . '</div>',
      ];
      return;
    }

    if ($this->options['type'] == 'textfield') {
      $terms = $this->value ? Term::loadMultiple(($this->value)) : [];
      $form['value'] = [
        '#title' => $this->options['limit'] ? $this->t('Select terms from vocabulary @voc', ['@voc' => $vocabulary->label()]) : $this->t('Select terms'),
        '#type' => 'textfield',
        '#default_value' => EntityAutocomplete::getEntityLabels($terms),
      ];

      if ($this->options['limit']) {
        $form['value']['#type'] = 'entity_autocomplete';
        $form['value']['#target_type'] = 'taxonomy_term';
        $form['value']['#selection_settings']['target_bundles'] = [$vocabulary->id()];
        $form['value']['#tags'] = TRUE;
        $form['value']['#process_default_value'] = FALSE;
      }
    }
    else {
      

$uri_reference = '<front>' . substr($uri_reference, 1);
      }

      $displayable_string = $uri_reference;
    }
    elseif ($scheme === 'entity') {
      [$entity_type, $entity_id] = explode('/', substr($uri, 7), 2);
      // Show the 'entity:' URI as the entity autocomplete would.       // @todo Support entity types other than 'node'. Will be fixed in       // https://www.drupal.org/node/2423093.       if ($entity_type == 'node' && $entity = \Drupal::entityTypeManager()->getStorage($entity_type)->load($entity_id)) {
        $displayable_string = EntityAutocomplete::getEntityLabels([$entity]);
      }
    }
    elseif ($scheme === 'route') {
      $displayable_string = ltrim($displayable_string, 'route:');
    }

    return $displayable_string;
  }

  /** * Gets the user-entered string as a URI. * * The following two forms of input are mapped to URIs: * - entity autocomplete ("label (entity id)") strings: to 'entity:' URIs; * - strings without a detectable scheme: to 'internal:' URIs. * * This method is the inverse of ::getUriAsDisplayableString(). * * @param string $string * The user-entered string. * * @return string * The URI, if a non-empty $uri was passed. * * @see static::getUriAsDisplayableString() */

class Name extends InOperator {

  protected $alwaysMultiple = TRUE;

  /** * The validated exposed input. */
  protected array $validated_exposed_input;

  protected function valueForm(&$form, FormStateInterface $form_state) {
    $users = $this->value ? User::loadMultiple($this->value) : [];
    $default_value = EntityAutocomplete::getEntityLabels($users);
    $form['value'] = [
      '#type' => 'entity_autocomplete',
      '#title' => $this->t('Usernames'),
      '#description' => $this->t('Enter a comma separated list of user names.'),
      '#target_type' => 'user',
      '#tags' => TRUE,
      '#default_value' => $default_value,
      '#process_default_value' => $this->isExposed(),
    ];

    $user_input = $form_state->getUserInput();
    

        // static::getEntityLabels().         $element['#default_value'] = [$element['#default_value']];
      }

      if ($element['#default_value']) {
        if (!(reset($element['#default_value']) instanceof EntityInterface)) {
          throw new \InvalidArgumentException('The #default_value property has to be an entity object or an array of entity objects.');
        }

        // Extract the labels from the passed-in entity objects, taking access         // checks into account.         return static::getEntityLabels($element['#default_value']);
      }
    }

    // Potentially the #value is set directly, so it contains the 'target_id'     // array structure instead of a string.     if ($input !== FALSE && is_array($input)) {
      $entity_ids = array_map(function Darray $item) {
        return $item['target_id'];
      }, $input);

      $entities = \Drupal::entityTypeManager()->getStorage($element['#target_type'])->loadMultiple($entity_ids);

      

/** * Returns an entity label in format needed by the EntityAutocomplete element. * * @param \Drupal\Core\Entity\EntityInterface $entity * A Drupal entity. * * @return string * A string that can be used as a value for EntityAutocomplete elements. */
  protected function getAutocompleteInput(EntityInterface $entity) {
    return EntityAutocomplete::getEntityLabels([$entity]);
  }

}