方法比较简单，没什么高深的应用，都是框架里面的东西，这里记录一下：
实体：UserEntity， 自增主键：F_Id
public class UserEntity : IEntity<UserEntity> {
public int F_Id { get; set; }
public string F_Account { get; set; }
public string F_RealName { get; set; }
public string F_NickName { get; set; }
}
调用：
UserEntity userEntity = new UserEntity ();
MyDbContext dbcontext = new MyDbContext();
dbcontext.Entry<UserEntity>(userEntity).State = System.Data.Entity.EntityState.Added;
dbcontext.SaveChanges();
dbcontext.Entry(userEntity);//返回插入的记录并注入到userEntity
int value = userEntity.F_Id;