Drupal 7 - 注意：未定义索引：und in include（）

I'm getting this error: Notice: Undefined index: und in include() (line 24 of /home/cliffdwellerproductions/dev.cliffdwellerdigital.com/Dahl/sites/all/themes/basic/templates/node--page2.tpl.php).

the code is:

if ($node->field_body_left !== NULL) : 
$text = trim($node->field_body_left['und']['0']['value']);
else:
$text = '';

Please help, as I haven't been able to define the variable...

Alf

Your $node->field_body_left variable is existent but it doesn't have an 'und' element.

It looks like you're attempting to check for an empty field, but you're using $field_body_left!==null which will only be false if the variable is literally null. When a drupal field is present but empty, it's usually equal to array(). Use != instead of !==, and then it will correctly detect both null variables and empty arrays and move on.

--

Extra info: If the variable had a value, its structure would be:

$field_body_left = array(
    'und' => array(
        0 => array (
             'value' => YOURVALUE
        )
    )
)

But since it doesn't have a value, its structure is:

$field_body_left = array()