C#在EntityFramework中实现事务回滚

    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                using (TransactionScope ts = new TransactionScope())
                {
                    using (CountryDetailsEntities db = new CountryDetailsEntities())
                    {
                        Country country = new Country();
                        country.CountryName = "USA";
                        db.Countries.Add(country);
                        db.SaveChanges();
                        if (country.CountryID > 0)
                        {
                            int a = 0;
                            int total = 10 / a;
                            State state = new State();
                            state.CountryID = country.CountryID;
                            state.StateName = "NewYork";
                            db.States.Add(state);
                            db.SaveChanges();
                        }
                    }
                    ts.Complete();
                }
                
            }
            catch (Exception ex)
            {
                throw;
            }
        }
    }