Returns the element id of the level that defines the bottom of the underlay range.
Namespace: Autodesk.Revit.DB
Assembly: RevitAPI (in RevitAPI.dll) Version: 25.3.0.0 (25.3.0.0)
Syntax
C#
public ElementId GetUnderlayBaseLevel()
Return Value
ElementIdIf InvalidElementId is returned, then the underlay base level is not set and no elements will be displayed as underlay.