[IfcConstructionMaterialResource.UsageRatio property 使用率 public IfcRatioMeasure UsageRatio { get; set; } 也可以看看 class IfcRatioMeasure class IfcConstructionMaterialResource 命名空间 Aspose.CAD.FileFormats.Ifc.IFC2X3.Entities 部件 Aspose.CAD]
