Share Email Facebook Twitter LinkedIn Categories.IsEmpty Property Whether or not the list of top-level categories is empty.Namespace: Autodesk.Revit.DBAssembly: RevitAPI (in RevitAPI.dll) Version: 26.4.0.0 (26.4.0.0) Syntax C# public override bool IsEmpty { get; }Property ValueBoolean See AlsoReferenceCategories ClassAutodesk.Revit.DB Namespace