Getting field data out of entities

EDIT: download the module that encapsulates this behaviour and does a lot more besides: read this blog.

The new field structure in Drupal 7 is very clever but also quite irritating when you want to get data out of a field in an entity, so I have written this handy routine which extracts field data:


/**
 * Returns field values as actual entities where possible,
 * also allows selection of individual items to be returned
 */
function field_fetch_field_values($entity_type, $entity, $field_name, $get_delta = NULL, $get_key = NULL) {
  $values = array();
  if (isset($entity->$field_name) && !empty($entity->$field_name)) {
    foreach (field_get_items($entity_type, $entity, $field_name) as $delta => $item) {
      $value = $item;
      $keys = array_keys($item);
      if (count($keys)==1) {
        $key = $keys[0];
        switch ($key) {
          case 'nid':
            $value = array_shift(entity_load('node', array($item[$key])));
            break;
          case 'uid':
            $value = array_shift(entity_load('user', array($item[$key])));
            break;
          case 'tid':
            $value = array_shift(entity_load('taxonomy_term', array($item[$key])));
            break;
          case 'vid':
            $value = array_shift(entity_load('taxonomy_vocabulary', array($item[$key])));
            break;
          case 'value':
            $value = $item['value'];
            break;
        }
      }
      else {
        if ($get_key && isset($item[$get_key])) {
          $value = $item[$get_key];
        }
        elseif (array_key_exists('value', $item)) {
          $value = isset($item['safe_value']) ? $item['safe_value'] : $item['value'];
        }
      }
      $values[$delta] = $value;
    }
  }
  if (is_numeric($get_delta)) {
    return isset($values[$get_delta]) ? $values[$get_delta] : NULL;
  }
  return $values;
}


Use it like this:

$terms = field_fetch_field_values('node', $node, 'field_myterms');

Extracts all the tids from the field and returns the actual terms, not the tids.

$term = field_fetch_field_values('node', $node, 'field_myterms', 0);

Returns just the first term.

$summary = field_fetch_field_values('node', $node, 'body', 0, 'safe_summary');


Returns only the summary from the body field, but does not create a summary if there isn't one.


$info = field_fetch_field_values('node', $node, 'field_myfiles', 0);


If field_myfiles contains uploaded file data you get the full file info array back, in this example just the first one.


There are probably cleverer ways of doing this (and you could do multiple entity_loads to make it more efficient) but I find this works well enough for normal day-to-day use.