Get node values from array with Drupal API?

Question

With Drupal API I found you can get the values of a node with noad_load like so:

$thisnode = node_load($nid = $child2, $vid = NULL, $reset = FALSE);

Now it is easy to echo the title in this way

$thisnode->title;

But the array begins to get quite complex when I try and get data from the custom image_thumbnail field because it is array within array. See the full printed array for one node:

stdClass Object ( [vid] => 4 [uid] => 1 [title] => Who we are [log] => [status] => 1 [comment] => 0 [promote] => 0 [sticky] => 0 [nid] => 4 [type] => level_2 [language] => und [created] => 1345561152 [changed] => 1346982536 [tnid] => 0 [translate] => 0 [revision_timestamp] => 1346982536 [revision_uid] => 1 [body] => Array ( [und] => Array ( [0] => Array ( [value] => blah blah blah [summary] => [format] => plain_text [safe_value] => 

blah blah blah
 [safe_summary] => ) ) ) [field_parent2] => Array ( [und] => Array ( [0] => Array ( [target_id] => 2 ) ) ) [field_level2_thumbnail_image] => Array ( [und] => Array ( [0] => Array ( [fid] => 4 [alt] => this is a photo [title] => this is a photo [width] => 308 [height] => 198 [uid] => 1 [filename] => article-image.png [uri] => public://article-image.png [filemime] => image/png [filesize] => 105660 [status] => 1 [timestamp] => 1346982536 [rdf_mapping] => Array ( ) ) ) ) [rdf_mapping] => Array ( [rdftype] => Array ( [0] => sioc:Item [1] => foaf:Document ) [title] => Array ( [predicates] => Array ( [0] => dc:title ) ) [created] => Array ( [predicates] => Array ( [0] => dc:date [1] => dc:created ) [datatype] => xsd:dateTime [callback] => date_iso8601 ) [changed] => Array ( [predicates] => Array ( [0] => dc:modified ) [datatype] => xsd:dateTime [callback] => date_iso8601 ) [body] => Array ( [predicates] => Array ( [0] => content:encoded ) ) [uid] => Array ( [predicates] => Array ( [0] => sioc:has_creator ) [type] => rel ) [name] => Array ( [predicates] => Array ( [0] => foaf:name ) ) [comment_count] => Array ( [predicates] => Array ( [0] => sioc:num_replies ) [datatype] => xsd:integer ) [last_activity] => Array ( [predicates] => Array ( [0] => sioc:last_activity_date ) [datatype] => xsd:dateTime [callback] => date_iso8601 ) ) [name] => slawrence10 [picture] => 0 [data] => b:0; )

What's the best way to extract for example alt from *field_level2_thumbnail_image*?

I can do it like so:

$thisnode->field_level2_thumbnail_image['und'][0]['alt'];

But is this stable? Will 'und' always be 0? Am I missing something here?

Answer 1

If it is for page view of some kind, I think you can maybe try for this more robust way of getting at field values:

$output = field_view_field('node', $node, 'field_name');

An important trick that shows one of the ways to deal with field data properly. Initially learned a while back off this site.

Another method of getting at the data I just thought of and use quite a bit in a recent project is entity api. Highly recommended add-on. Consider the following borrowed snippet that shows how to deal with mail field. Other fields are the same.

   $wrapper = entity_metadata_wrapper('node', $node);
   $wrapper->author->mail->value();

To update the user's mail address one could use

   $wrapper->author->mail->set('[email protected]');

   or

   $wrapper->author->mail = '[email protected]';

Last but not least, there are still yet other alternatives surely?

Best practice for language key for "und" in hook_form_alter. I did not flag as duplicate as I did not check into detail if other question was detailed or not, but it should be enough to give you ideas.

Good-luck.

Answer 2

It is sorta like this:

$node->FIELDNAME[LANGUAGE][DELTA][INFORMATION]

So, in your example, it would be:

$node->field_level2_thumbnail_image['und'][0]['filename'];

Some details:

['und'] =======> LANGUAGE_NONE or none defined for this node
[0] ===========> The first value.  If this were a multiple value field, you could have more
['filename'] ==> The filename you are looking for. 
['alt'] =======> The alt tag