Subelement

Description:
An object that represents an element or a subelement within the Autodesk Revit project.

Remarks:

Subelements provide a way for parts of an element to behave as though they were real elements without incurring the overhead of adding more full elements to the model.

Many Revit features (for example parameters, schedules, and tags) were designed to operate on Elements. As a result, the Revit code needs to represent objects as Elements for them to participate in those features. This can lead to scalability problems, because every Element adds overhead and adding many Elements may decrease the performance of the model. An alternative is to use Subelements. An element can expose a set of "Subelements" that it contains, specifying characteristics like their category and parameters, and certain Revit capabilities will treat those Subelements the same as ordinary Elements. For example, a Subelement may contribute geometry to the main element and may be able to be selected independently of its parent Element. It will possibly have its own (settable) type as well as an assigned category which can be different from its parent Element.

In the API, the new Subelement class is used to refer to either an Element or a specific subelement of a given Element. It is typically directly related to a Reference to either the Element or the specific subelement. Note that creation of new Subelements for a given element is not done generically. Instead, the given Element may provide the ability to modify it's definition, resulting in the creation of new Subelements.

Examples of Elements which may have Subelements in practice include:

RebarContainer
Rebar
FabricSheet
Stairs elements which make up MultistoryStairs elements
Railing
[!:Autodesk::Revit::DB::Architecture::ContinuousRail]

To get access to a particular Subelement, you may use any of the following:

Create(Document, Reference)
IsValidSubelementReference(Document, Reference)
Autodesk.Revit.DB.Document.GetSubelement(Autodesk.Revit.DB.Reference) if you have a Reference to a Subelement.
Autodesk.Revit.DB.Document.GetSubelement(String) if you have a unique id of a Subelement.
GetSubelements()

Inheritance Hierarchy:
System.Object
Autodesk.Revit.DB.Subelement

public class Subelement : IDisposable

Public Class Subelement
	Implements IDisposable

public ref class Subelement : IDisposable

type Subelement = 
    class
        interface IDisposable
    end

Name	Return Type	Description	Inherited From
M CanHaveTypeAssigned()	Boolean	Identifies if the subelement can have a type assigned.
M ChangeTypeId(ElementId)	None	Changes the type of the subelement.
M Create(Document, Reference)	Subelement	Creates an object representing element or subelement.
M Dispose()	None	Releases all resources used by the Subelement
M Equals	None	Determines whether the specified object is equal to the current object. (Inherited from Object )	Object
M GetAllParameters()	IList<ElementId>	Returns all parameters of this subelement.
M GetBoundingBox(View)	BoundingBoxXYZ	Retrieves a box that circumscribes all geometry of the subelement.
M GetGeometryObject(View)	GeometryObject	Retrieve one geometric primitive representing given subelement.
M GetHashCode	None	Serves as the default hash function. (Inherited from Object )	Object
M GetParameterValue(ElementId)	ParameterValue	Obtains the current parameter value of this subelement given a parameter id.
M GetReference()	Reference	Obtains the reference to this subelement.
M GetType	None	Gets the Type of the current instance. (Inherited from Object )	Object
M GetValidTypes()	ISet<ElementId>	Obtains a set of types that are valid for this subelement.
M HasParameter(ElementId)	Boolean	Checks if this subelement have given parameter.
M IsParameterModifiable(ElementId)	Boolean	Checks if given parameter of this subelement is modifiable.
M IsValidSubelementReference(Document, Reference)	Boolean	Checks if given Reference identifies either a valid element or subelement.
M IsValidType(ElementId)	Boolean	Checks if given type is valid for this subelement.
M SetParameterValue(ElementId, ParameterValue)	None	Sets a new parameter value of this subelement given a parameter id.
M ToString	None	Returns a string that represents the current object. (Inherited from Object )	Object

Name	Return Type	Description
P Category	Category	Retrieves a Category object that represents the category or sub category of the subelement.
P Document	Document	The document in which the subelement resides.
P Element	Element	The element in which the subelement resides.
P IsValidObject	Boolean	Specifies whether the .NET object represents a valid Revit entity.
P TypeId	ElementId	The identifier of this subelement's type.
P UniqueId	string	A stable unique identifier for this subelement within the document.