Revit 2025 API
View |
Sets the underlay base and underlay top to the specified levels.
Namespace: Autodesk.Revit.DB
Assembly: RevitAPI (in RevitAPI.dll) Version: 25.0.0.0 (25.0.0.0)
Syntax
public void SetUnderlayRange( ElementId baseLevelId, ElementId topLevelId )
Public Sub SetUnderlayRange ( baseLevelId As ElementId, topLevelId As ElementId )
public: void SetUnderlayRange( ElementId^ baseLevelId, ElementId^ topLevelId )
member SetUnderlayRange : baseLevelId : ElementId * topLevelId : ElementId -> unit
Parameters
- baseLevelId ElementId
- The element id of a level in the project or InvalidElementId. If InvalidElementId, then the underlay base level is not set and no elements will be displayed as underlay.
- topLevelId ElementId
- The element id of a level in the project or InvalidElementId. If InvalidElementId, then the underlay range is unbounded.

Exception | Condition |
---|---|
ArgumentException | The ElementId baseLevelId does not correspond to a Level in the project. -or- The ElementId topLevelId does not correspond to a Level in the project. -or- The elevation of level topLevelId must be greater than the elevation of level baseLevelId. |
ArgumentNullException | A non-optional argument was null |

private void ViewUnderlay(ViewPlan planView, ElementId topLevelId, ElementId baseLevelId) { if (planView.GetUnderlayOrientation() == UnderlayOrientation.LookingDown) { if (planView.GetUnderlayTopLevel() != topLevelId) { planView.SetUnderlayRange(baseLevelId, topLevelId); } planView.SetUnderlayOrientation(UnderlayOrientation.LookingUp); } }
Private Sub ViewUnderlay(planView As ViewPlan, topLevelId As ElementId, baseLevelId As ElementId) If planView.GetUnderlayOrientation() = UnderlayOrientation.LookingDown Then If planView.GetUnderlayTopLevel() <> topLevelId Then planView.SetUnderlayRange(baseLevelId, topLevelId) End If planView.SetUnderlayOrientation(UnderlayOrientation.LookingUp) End If End Sub
No code example is currently available or this language may not be supported.
No code example is currently available or this language may not be supported.
See Also