The ItemFactoryBase object is used to create new instances of elements within the Autodesk Revit document. 
   Namespace:   Autodesk.Revit.Creation  
  Assembly:   RevitAPI  (in RevitAPI.dll) Version: 2015.0.0.0 (2015.0.0.0) 
Syntax
Remarks
 The ItemFactoryBase object is a utility object that is used to create new instances of elements within the Autodesk Revit document. This class holds common methods used in both project documents and family documents. 
 Inheritance Hierarchy
  System Object  
Autodesk.Revit.DB APIObject
Autodesk.Revit.Creation ItemFactoryBase
Autodesk.Revit.Creation Document
Autodesk.Revit.Creation FamilyItemFactory
 
 Autodesk.Revit.DB APIObject
Autodesk.Revit.Creation ItemFactoryBase
Autodesk.Revit.Creation Document
Autodesk.Revit.Creation FamilyItemFactory