[IfcAnnotationSurface.Item property 项目 public IfcGeometricRepresentationItem this { get; set; } 也可以看看 class IfcGeometricRepresentationItem class IfcAnnotationSurface 命名空间 Aspose.CAD.FileFormats.Ifc.IFC2X3.Entities 部件 Aspose.CAD]
