src/Kunstmaan/FormBundle/Entity/FormSubmissionFieldTypes/ChoiceFormSubmissionField.php
public function isNull()
    {
        $values = $this->getValue();
        if (is_array($values)) {
            return empty($values) || count($values) <= 0;
        } elseif (is_string($values)) {
            return !isset($values) || trim($values) === '';
        } else {
            return is_null($values);
        }
    }
public function isNull()
    {
        $values = $this->getValue();
        if (is_array($values)) {
            return empty($values) || count($values) <= 0;
        } elseif (is_string($values)) {
            return !isset($values) || trim($values) === '';
        } else {
            return is_null($values);
        }
    }
public function isNull ( ) { $ values = $ this -> getValue ( ) ; if ( is_array ( $ values ) ) { return empty ( $ values ) || count ( $ values ) <= 0 ; } elseif ( is_string ( $ values ) ) { return ! isset ( $ values ) || trim ( $ values ) === '' ; } else { return is_null ( $ values ) ; } }
Checks if the value of this field is null

@return bool
Checks if the value of this field is null