EntityObject::sysIsChanged

public function sysIsChanged($fieldName)
{
	$fieldName = StringHelper::strtoupper($fieldName);
	$field = $this->entity->getField($fieldName);

	if ($field instanceof ObjectField)
	{
		$currentValue = $this->_currentValues[$fieldName];
		$actualValue = $this->_actualValues[$fieldName];

		return $field->encode($currentValue) !== $field->encode($actualValue);
	}

	return array_key_exists($fieldName, $this->_currentValues);
}