Error when I edit a block: Notice: Undefined index: und in eval() I don't understand why I put $node-&gt;field_test['und'][0]['value'] appears the next error:


  Notice: Undefined index: und in eval() 


The field "field_test" is a boolean field. The code is the following one:

$node = node_load(153);    
if ($node-&gt;field_test['und'][0]['value'] == 1) { 
  echo "test";
}


What is my error?
You must pay attention to the node's language. 'und' is for nodes which don't have a language set. If you set one, then the values will be in 'en' or 'de' or whatever the node's language code is.