[IfcBooleanResult.FirstOperand property FirstOperand public IfcBooleanOperand FirstOperand { get; set; } 也可以看看 class IfcBooleanOperand class IfcBooleanResult 命名空间 Aspose.CAD.FileFormats.Ifc.IFC2X3.Entities 部件 Aspose.CAD]
