使用标记方式entry方法进行删除和修改

Dbcontext 有Entry方法 用他来改变集合里面每一项的状态

   //增   不推荐            PeopleEntities context = new PeopleEntities();            //context.Entry<Student>(new Student() { Name = "heyuke", Age = 18 }).State = EntityState.Added;            //context.SaveChanges();            //删   推荐 但必须标明主键            //context.Entry<Student>(new Student() { Id=5,Name = "heyuke", Age = 18 }).State = EntityState.Deleted;            //context.SaveChanges();            //改 推荐            context.Entry<Student>(new Student() { Id=1,Name = "hehe"}).State = EntityState.Modified;            context.SaveChanges();