EntityObject::getId

public function getId()
{
	if (array_key_exists('ID', $this->_currentValues))
	{
		return $this->_currentValues['ID'];
	}
	elseif (array_key_exists('ID', $this->_actualValues))
	{
		return $this->_actualValues['ID'];
	}
	elseif (!$this->entity->hasField('ID'))
	{
		throw new SystemException(sprintf(
			'Unknown method `%s` for object `%s`', 'getId', get_called_class()
		));
	}
	else
	{
		return null;
	}
}