function book_export

7.x book_export($type, $nid)

Menu callback; Generates representations of a book page and its children.

The function delegates the generation of output to helper functions. The function name is derived by prepending 'book_export_' to the given output type. So, e.g., a type of 'html' results in a call to the function book_export_html().


$type: A string encoding the type of output requested. The following types are currently supported in book module:

  • html: Printer-friendly HTML.

Other types may be supported in contributed modules.

$nid: An integer representing the node id (nid) of the node to export

Return value

A string representing the node and its children in the book hierarchy in a format determined by the $type parameter.

See also


1 string reference to 'book_export'
book_menu in drupal/modules/book/book.module
Implements hook_menu().


drupal/modules/book/, line 47
User page callbacks for the book module.


function book_export($type, $nid) {
  // Check that the node exists and that the current user has access to it.
  $node = node_load($nid);
  if (!$node) {
    return MENU_NOT_FOUND;
  if (!node_access('view', $node)) {

  $type = drupal_strtolower($type);

  $export_function = 'book_export_' . $type;

  if (function_exists($export_function)) {
    print call_user_func($export_function, $nid);
  else {
    drupal_set_message(t('Unknown export format.'));