public void addhvv(List <CoursesStudentDetailtObject> lst) { if (lst == null && lst.Count <= 0) { return; } var dathem = new CoursesStudentDetailtBCL().GetAll().Where(q => q.CJId.Equals(lst[0].CJId)); var bcl = new CoursesStudentDetailtBCL(); foreach (var item in lst) { var hv = dathem.FirstOrDefault(m => m.StudetId.Equals(item.StudetId)); var ob = new CoursesStudentDetailtObject() { CJId = lst[0].CJId, Description = item.Description, StudetId = item.StudetId }; if (hv == null && item.Selected) { ob.ScsId = Guid.NewGuid(); bcl.Insert(ob); } else if (hv != null) { hv.Description = ob.Description; if (item.Selected) { bcl.Update(hv); } else { bcl.Delete(hv.ScsId); } } } }