Returns the database level document represented by this UI-level document.
Namespace: Autodesk.Revit.UI
Assembly: RevitAPIUI (in RevitAPIUI.dll) Version: 2015.0.0.0 (2015.0.0.0)
Namespace: Autodesk.Revit.UI
Assembly: RevitAPIUI (in RevitAPIUI.dll) Version: 2015.0.0.0 (2015.0.0.0)