15----EFContext对象从数据槽获取---单例模式

class Program
    {
        static void Main(string[] args)
        {
            //DbContext context = ContextFactory.GetContext();
            //OrderInfo oi = new OrderInfo()
            //{
            //     OrderTitle="三星手机"
            //};
            //oi.CustomerInfo = new CustomerInfo()
            //{
            //     CustomerName="淳于琼",
            //     CustomerDate=DateTime.Now
            //};
            //context.Set<OrderInfo>().Add(oi);
            //context.SaveChanges();
            //Console.WriteLine("OK");
            //Console.ReadKey();

            //测试，
            AddCustomerInfo();
            AddOrderInfo();
            Save();
            Console.WriteLine("OK");
            Console.ReadKey();

        }
        /// <summary>
        /// 
        /// </summary>
        private static void Save()
        {
            DbContext context = ContextFactory.GetContext();
            context.SaveChanges();
        }

        private static void AddCustomerInfo()
        {
            DbContext context = ContextFactory.GetContext();
            context.Set<CustomerInfo>().Add(new CustomerInfo()
            {
                CustomerName = "大张伟",
                CustomerDate = DateTime.Now
            });

        }

        private static void AddOrderInfo()
        {
            DbContext context = ContextFactory.GetContext();
            context.Set<OrderInfo>().Add(new OrderInfo()
            {
                 OrderTitle="七星宝刀",
                 CustomerId=7
            });
        }
    }
    /// <summary>
    /// 获取上下文对象的类
    /// </summary>
    public static class ContextFactory
    {
        public static DbContext GetContext()
        {
            //从数据槽中获取上下文对象，保证对象的单一
            DbContext context = CallContext.GetData("DbContext") as DbContext;
            if (context == null)
            {
                //当数据槽中不存在的时候。创建一个上下文对象并把它放在数据槽中
                context = new EFTestEntities();
                CallContext.SetData("DbContext", context);
            }
            return context;
        }
    }