EF 用CallContext上下文管理

public class ObjectContextFactory
    {
        private static CIK_NewsEntities context;
        public static DbContext GetContext()
        {
            //从CallContext数据槽中获取EF上下文
            context = CallContext.GetData(typeof(ObjectContextFactory).FullName) as CIK_NewsEntities;
            if (context==null)
            {
                //如果CallContext数据槽中没有EF上下文，则创建EF上下文，并保存到CallContext数据槽中
                context = new CIK_NewsEntities();
                CallContext.SetData(typeof(ObjectContextFactory).FullName, context);
            }
            return context;
        }

    }