P

AreaBasedLoadBoundaryLineData.TopLevelId

Description:
The top level id of the area based load boundary line.

Remarks:
The top level's elevation cannot be lower than the bottom level.

public ElementId TopLevelId { get; set; }

Public Property TopLevelId As ElementId
Get
Set

public:
property ElementId^ TopLevelId {
	ElementId^ get ();
	void set (ElementId^ value);
}

Autodesk.Revit.Exceptions.ArgumentException

When setting this property: The ElementId levelId cannot be used as the top level. The ElementId levelId is not a Level or it's elevation is lower than the bottom level's elevation.
Autodesk.Revit.Exceptions.ArgumentNullException

When setting this property: A non-optional argument was null