6.x book.module book_form_alter(&$form, $form_state, $form_id)

Implementation of hook_form_alter(). Adds the book fieldset to the node form.

See also




modules/book/book.module, line 283
Allows users to structure the pages of a site in a hierarchy or outline.


function book_form_alter(&$form, $form_state, $form_id) {
  if (isset($form['type']) && isset($form['#node']) && $form['type']['#value'] . '_node_form' == $form_id) {

    // Add elements to the node form
    $node = $form['#node'];
    $access = user_access('administer book outlines');
    if (!$access) {
      if (user_access('add content to books') && (!empty($node->book['mlid']) && !empty($node->nid) || book_type_is_allowed($node->type))) {

        // Already in the book hierarchy or this node type is allowed
        $access = TRUE;
    if ($access) {
      _book_add_form_elements($form, $node);
      $form['book']['pick-book'] = array(
        '#type' => 'submit',
        '#value' => t('Change book (update list of parents)'),
        // Submit the node form so the parent select options get updated.
        // This is typically only used when JS is disabled.  Since the parent options
        // won't be changed via AJAX, a button is provided in the node form to submit
        // the form and generate options in the parent select corresponding to the
        // selected book.  This is similar to what happens during a node preview.
        '#submit' => array(
        '#weight' => 20,