[IfcExternalReferenceRelationship.RelatingReference property RelatingReference public IfcExternalReference RelatingReference { get; set; } 也可以看看 class IfcExternalReference class IfcExternalReferenceRelationship 命名空间 Aspose.CAD.FileFormats.Ifc.IFC4.Entities 部件 Aspose.CAD]