Error Message on special CustomField Query

[PeterD]

I have some old listings in a category (listing type) to which I have assigned new fields.

Everything works so far, but when I work with the following query I get an error on all listings where the field is not filled in

<?php if (in_array('option-value', $CustomFields->fieldValue('jr_fieldname',$listing))): ?>

  <!-- Conditional output -->

<?php endif; ?>

Error:
 

0 in_array(): Argument #2 ($haystack) must be of type array, bool given

 

[Alejandro]

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[PeterD]

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