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

Namespace: Autodesk.Revit.DB.Electrical
Assembly: RevitAPI (in RevitAPI.dll) Version: 24.0.0.0 (24.0.0.0)
Since: 2023

Syntax

C#
`public ElementId TopLevelId { get; set; }`

Visual Basic
`Public Property TopLevelId As ElementId Get Set`

Visual C++
`public: property ElementId^ TopLevelId { ElementId^ get (); void set (ElementId^ value); }`

Remarks

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

Exception	Condition
Autodesk.Revit.ExceptionsArgumentException	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.ExceptionsArgumentNullException	When setting this property: A non-optional argument was null