Form constructor to confirm removal of a node from a book.
Drupal\node\Node $node: The node to delete.
function book_remove_form($form, &$form_state, Node $node) {
$form['#node'] = $node;
$title = array(
'%title' => $node
->label(),
);
if ($node->book['has_children']) {
$description = t('%title has associated child pages, which will be relocated automatically to maintain their connection to the book. To recreate the hierarchy (as it was before removing this page), %title may be added again using the Outline tab, and each of its former child pages will need to be relocated manually.', $title);
}
else {
$description = t('%title may be added to hierarchy again using the Outline tab.', $title);
}
return confirm_form($form, t('Are you sure you want to remove %title from the book hierarchy?', $title), 'node/' . $node->nid, $description, t('Remove'));
}