在自定义 twig 模板中获取书名

Question

I'd like to display the main Book title on all pages of a book, instead of only the current page's title. However, I can't find a way to print this Book title in my Twig template.

How can I get the main Book title and print it in a custom twig template?

Answer 1

In your hook_preprocess_node

function hook_preprocess_node(&$variables) {
    // Get node object;
    $node = $variables['node'];
    $node_id = $node->id();
    $entity = \Drupal::entityTypeManager()->getStorage('node')->load($node_id);
    if (isset($entity->book)) {
    $book_id = $entity->book['p1'];
    $book_parent_entity = \Drupal::entityTypeManager()->getStorage('node')->load($book_id);
    $title = $book_parent_entity->getTitle();
    $variables['book_title'] = $title;
    }