deserialize_xld反序列化扩展线描述read_contour_xld_arc_info读取轮廓扩展线描述ARC信息read_contour_xld_dxf读取轮廓扩展线描述DXFread_polygon_xld_arc_info读取多边形扩展线描述ARC信息read_polygon_xld_dxf读取多边形扩展线描述DXFserialize_xld序列化扩展线描述write_contour_xld_arc_info写入轮廓扩展线描述ARC信息write_contour_xld_dxf写入轮廓扩展线描述DXFwrite_polygon_xld_arc_info写入多边形扩展线描述ARC信息write_polygon_xld_dxf写入多边形扩展线描述DXF