Entity::addFilterStringValue

private function addFilterStringValue(array &$result, array $filter, $fieldId, array $field)
{
	if (isset($filter[$fieldId]) && is_string($filter[$fieldId]))
	{
		$value = trim($filter[$fieldId]);
		if ($value !== '')
		{
			$operator = $this->getFilterOperator($field, 'default');
			if (is_string($operator))
				$fieldId = $operator.$fieldId;
			unset($operator);
			$this->addFilterItems($result, [$fieldId => $value], $field);
		}
		unset($value);
	}
}