yii\db\QueryTrait::isEmpty PHP 메소드

isEmpty() 보호된 메소드

The value is considered "empty", if one of the following conditions is satisfied: - it is null, - an empty string (''), - a string containing only whitespace characters, - or an empty array.
protected isEmpty ( mixed $value ) : boolean
$value mixed
리턴 boolean if the value is empty
    protected function isEmpty($value)
    {
        return $value === '' || $value === [] || $value === null || is_string($value) && trim($value) === '';
    }