Perform field validation against form-submitted field values.

There are two levels of validation for fields in forms: widget validation, and field validation.

• Widget validation steps are specific to a given widget's own form structure and UI metaphors. They are executed through FAPI's #element_validate property during normal form validation.
• Field validation steps are common to a given field type, independently of the specific widget being used in a given form. They are defined in the field type's implementation of hook_field_validate().

This function performs field validation in the context of a form submission. It converts field validation errors into form errors on the correct form elements. Fieldable entity types should call this function during their own form validation function.

Parameters

$entity_type: The type of $entity; e.g. 'node' or 'user'.

$entity: The entity being submitted. The 'bundle', 'id' and (if applicable) 'revision' keys should be present. The actual field values will be read from $form_state['values'].

$form: The form structure where field elements are attached to. This might be a full form structure, or a sub-element of a larger form.

$form_state: An associative array containing the current state of the form.

array $options: An associative array of additional options. See _field_invoke() for details.

Related topics

File

drupal-7.x/modules/field/field.attach.inc, line 837

Field attach API, allowing entities (nodes, users, ...) to be 'fieldable'.

Code

function field_attach_form_validate($entity_type, $entity, $form, &$form_state, $options = array()) {
  // Validate $options since this is a new parameter added after Drupal 7 was
  // released.
  $options = is_array($options) ? $options : array();

  // Extract field values from submitted values.
  _field_invoke_default('extract_form_values', $entity_type, $entity, $form, $form_state);

  // Perform field_level validation.
  try {
    field_attach_validate($entity_type, $entity, $options);
  }
  catch (FieldValidationException $e) {
    // Pass field-level validation errors back to widgets for accurate error
    // flagging.
    foreach ($e->errors as $field_name => $field_errors) {
      foreach ($field_errors as $langcode => $errors) {
        $field_state = field_form_get_state($form['#parents'], $field_name, $langcode, $form_state);
        $field_state['errors'] = $errors;
        field_form_set_state($form['#parents'], $field_name, $langcode, $form_state, $field_state);
      }
    }
    _field_invoke_default('form_errors', $entity_type, $entity, $form, $form_state, $options);
  }
}