function form_process_machine_name

Processes a machine-readable name form element.

Parameters

$element: The form element to process. Properties used:

  • #machine_name: An associative array containing:

    • exists: A callable to invoke for checking whether a submitted machine name value already exists. The submitted value is passed as an argument. In most cases, an existing API or menu argument loader function can be re-used. The callback is only invoked, if the submitted value differs from the element's #default_value.
    • source: (optional) The #array_parents of the form element containing the human-readable name (i.e., as contained in the $form structure) to use as source for the machine name. Defaults to array('label').
    • label: (optional) A text to display as label for the machine name value after the human-readable name form element. Defaults to "Machine name".
    • replace_pattern: (optional) A regular expression (without delimiters) matching disallowed characters in the machine name. Defaults to '[^a-z0-9_]+'.
    • replace: (optional) A character to replace disallowed characters in the machine name via JavaScript. Defaults to '_' (underscore). When using a different character, 'replace_pattern' needs to be set accordingly.
    • error: (optional) A custom form error message string to show, if the machine name contains disallowed characters.
    • standalone: (optional) Whether the live preview should stay in its own form element rather than in the suffix of the source element. Defaults to FALSE.
  • #maxlength: (optional) Should be set to the maximum allowed length of the machine name. Defaults to 64.
  • #disabled: (optional) Should be set to TRUE in case an existing machine name must not be changed after initial creation.

Related topics

1 string reference to 'form_process_machine_name'
system_element_info in drupal/core/modules/system/system.module
Implements hook_element_info().

File

drupal/core/includes/form.inc, line 3763
Functions for form and batch generation and processing.

Code

function form_process_machine_name($element, &$form_state) {

  // We need to pass the langcode to the client.
  $language = language(Language::TYPE_INTERFACE);

  // Apply default form element properties.
  $element += array(
    '#title' => t('Machine-readable name'),
    '#description' => t('A unique machine-readable name. Can only contain lowercase letters, numbers, and underscores.'),
    '#machine_name' => array(),
    '#field_prefix' => '',
    '#field_suffix' => '',
    '#suffix' => '',
  );

  // A form element that only wants to set one #machine_name property (usually
  // 'source' only) would leave all other properties undefined, if the defaults
  // were defined in hook_element_info(). Therefore, we apply the defaults here.
  $element['#machine_name'] += array(
    'source' => array(
      'label',
    ),
    'target' => '#' . $element['#id'],
    'label' => t('Machine name'),
    'replace_pattern' => '[^a-z0-9_]+',
    'replace' => '_',
    'standalone' => FALSE,
    'field_prefix' => $element['#field_prefix'],
    'field_suffix' => $element['#field_suffix'],
  );

  // By default, machine names are restricted to Latin alphanumeric characters.
  // So, default to LTR directionality.
  if (!isset($element['#attributes'])) {
    $element['#attributes'] = array();
  }
  $element['#attributes'] += array(
    'dir' => 'ltr',
  );

  // The source element defaults to array('name'), but may have been overidden.
  if (empty($element['#machine_name']['source'])) {
    return $element;
  }

  // Retrieve the form element containing the human-readable name from the
  // complete form in $form_state. By reference, because we may need to append
  // a #field_suffix that will hold the live preview.
  $key_exists = NULL;
  $source = NestedArray::getValue($form_state['complete_form'], $element['#machine_name']['source'], $key_exists);
  if (!$key_exists) {
    return $element;
  }
  $suffix_id = $source['#id'] . '-machine-name-suffix';
  $element['#machine_name']['suffix'] = '#' . $suffix_id;
  if ($element['#machine_name']['standalone']) {
    $element['#suffix'] .= ' <small id="' . $suffix_id . '">&nbsp;</small>';
  }
  else {

    // Append a field suffix to the source form element, which will contain
    // the live preview of the machine name.
    $source += array(
      '#field_suffix' => '',
    );
    $source['#field_suffix'] .= ' <small id="' . $suffix_id . '">&nbsp;</small>';
    $parents = array_merge($element['#machine_name']['source'], array(
      '#field_suffix',
    ));
    NestedArray::setValue($form_state['complete_form'], $parents, $source['#field_suffix']);
  }
  $js_settings = array(
    'type' => 'setting',
    'data' => array(
      'machineName' => array(
        '#' . $source['#id'] => $element['#machine_name'],
      ),
      'langcode' => $language->langcode,
    ),
  );
  $element['#attached']['library'][] = array(
    'system',
    'drupal.machine-name',
  );
  $element['#attached']['js'][] = $js_settings;
  return $element;
}