private IManageFile GetManageFile(EnumType fileType) { IStudentFactory abstractFactory; switch (fileType) { case EnumType.TXT: { abstractFactory = new TxtFactory(); return(abstractFactory.Create()); } case EnumType.XML: { abstractFactory = new XmlFactory(); return(abstractFactory.Create()); } default: { abstractFactory = new JsonFactory(); return(abstractFactory.Create()); } } }