private void detach_files(files entity)
		{
			this.SendPropertyChanging();
			entity.file_category = null;
		}
		private void attach_files(files entity)
		{
			this.SendPropertyChanging();
			entity.file_category = this;
		}
 partial void Updatefiles(files instance);
 partial void Deletefiles(files instance);
 partial void Insertfiles(files instance);