Returns the list of element ids that are not used. The list of unused element ids may include elements that can't be deleted.
Namespace: Autodesk.Revit.DB
Assembly: RevitAPI (in RevitAPI.dll) Version: 26.1.0.0 (26.1.0.34)
Syntax
C#
public ISet<ElementId> GetAllUnusedElements( ISet<ElementId> categories )
Parameters
Return Value
ISet<ElementId>Unused element ids.
Exceptions
Exception | Condition |
---|---|
ArgumentNullException | A non-optional argument was null |
Remarks
This method returns unused element ids that are available in the Purge Unused window in the Revit, including elements that can't be deleted. To get unused elements that do not have a category assigned add INVALID to the collection of categories. If the input categories collection is empty, the method returns all unused elements in the document.Example
C#
public void GetAllUnusedElements(Autodesk.Revit.DB.Document document) { // Get all unused elements in the document var allUnusedElementIds = document.GetAllUnusedElements(new HashSet<ElementId>()); // Get unused elements without a category var unusedElementIdsWithNoCategory = document.GetAllUnusedElements(new HashSet<ElementId>() { new ElementId(BuiltInCategory.INVALID) }); // Get unused wall and floors types HashSet<ElementId> categoriesToPurge = new HashSet<ElementId> { new ElementId(BuiltInCategory.OST_Walls), new ElementId(BuiltInCategory.OST_Floors) }; var unusedElementIds = document.GetAllUnusedElements(categoriesToPurge); }
VB
Public Sub GetAllUnusedElements(ByVal document As Document) ' Get all unused elements in the document Dim allUnusedElementIds = document.GetAllUnusedElements(New HashSet(Of ElementId)()) ' Get unused elements without a category Dim unusedElementIdsWithNoCategory = document.GetAllUnusedElements(New HashSet(Of ElementId)() From { New ElementId(BuiltInCategory.INVALID) }) ' Get unused wall and floors types Dim categoriesToPurge As HashSet(Of ElementId) = New HashSet(Of ElementId) From { New ElementId(BuiltInCategory.OST_Walls), New ElementId(BuiltInCategory.OST_Floors) } Dim unusedElementIds = document.GetAllUnusedElements(categoriesToPurge) End Sub