The family manager object to manage the family types and parameters in family document.
Namespace: Autodesk.Revit.DB
Assembly: RevitAPI (in RevitAPI.dll) Version: 18.0.0.0 (18.0.0.420)
Namespace: Autodesk.Revit.DB
Assembly: RevitAPI (in RevitAPI.dll) Version: 18.0.0.0 (18.0.0.420)