public void Soct(Guid LoaiCt, int thang, int nam) { if (VnsLoaiChungTuService == null) { VnsLoaiChungTuService = (IVnsLoaiChungTuService)ObjectFactory.GetObject("VnsLoaiChungTuService"); } List <String> lst_str = new List <String>(); lst_str.AddRange(this.VnsLoaiChungTuService.GetSoCT_prefix(LoaiCt, thang, nam)); string _thang = thang.ToString().Length == 1?string.Format("0{0}", thang):thang.ToString(); if (lst_str != null) { SO_CHUNG_TU = string.Format("{0}/{1}", _thang, lst_str[0] + lst_str[1]); } }