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空对象模式

 2016/7/23 5:33:09  流年、落了誰  程序员俱乐部  我要评论(0)
  • 摘要:在开发业务层数据的时候,我总是担心数据层给我返回的对象实例为null。所以,每次使用数据层返回的对象实例我都要判断下是否为nullUserRepositoryrespository=newUserRepository();varuser=respository.GetById("008");if(user!=null){user.SayHello();}虽然这样是避免了因为空值引发异常的问题,但是这样增加了客户端代码的很多工作量,而且一旦某个地方忘记判断,我的代码就会出现空异常
  • 标签:模式

  在开发业务层数据的时候,我总是担心数据层给我返回的对象实例为null。

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" alt="" width="500" />

  所以,每次使用数据层返回的对象实例我都要判断下是否为null

  UserRepository respository = new UserRepository();
  var user = respository.GetById("008");
  if (user!=null)
  {
      user.SayHello();
  }

   虽然这样是避免了因为空值引发异常的问题,但是这样增加了客户端代码的很多工作量,而且一旦某个地方忘记判断,我的代码就会出现空异常;为了解决这个问题,我们引入了空对象模式,将空对象扼杀在数据的源头

    public interface IUser
    {
        void SayHello();
    }
    public class User : IUser
    {
        public string Id { get; private set; }

        public User(string id)
        {
            Id = id;
        }

        public void SayHello()
        {
            Console.WriteLine("{0}:Hello", Id);
        }
    }
    public class NullUser : IUser
    {
        public void SayHello()
        {
            //对于空对象实例来说,它的任何方法都应该不用做任何处        }
    }
    public class UserRepository
    {
        private ICollection<User> users;

        public UserRepository()
        {
            users = new List<User>() {
                new User("001"),
                new User("002"),
                new User("003"),
                new User("004"),
                new User("005")
            };
        }

        public IUser GetById(string userId)
        {
            IUser user = users.SingleOrDefault(s => s.Id == userId);
            if (user == null)//检查User的实例是否为null,如果是返回一个特殊的Iuser
            {
                user = new NullUser();
            }
            return user;
        }
    }

  在上面的代码中,我们在数据层中直接就判断了user实例是不是为null,如果为null,就返回一个用作null值处理的对象实例

 static void Main(string[] args)
 {
     UserRepository respository = new UserRepository();
     var user = respository.GetById("008");
     user.SayHello();
     user = respository.GetById("003");
     user.SayHello();
     Console.ReadLine();
 }

  现在妈妈再也不用担心我调用数据层的对象实例报空引用了,当然这种方式并不仅限于在数据层使用

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" 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