收集的Asp.Net面试程序代码

来源：互联网发布：网络层协议有哪些作用编辑：程序博客网时间：2024/04/28 17:30

1.一列数的规则如下: 1、1、2、3、5、8、13、21、34......

求第30位数是多少，用递归算法实现。(C#语言)

代码：

     public static int Foo(int i)
    {
        if (i <= 0)
        {
            return 0;
        }
        else if ((i > 0) && (i <= 2))
        {
            return 1;
        }
        else
        {
            return Foo(i - 1) + Foo(i - 2);
        }
    }

调用方法： int i = int.Parse(TextBox1.Text);
TextBox2.Text = Foo(i).ToString();

2. 程序设计: 猫大叫一声，所有的老鼠都开始逃跑，主人被惊醒。(C#语言)

要求： 1.）要有联动性，老鼠和主人的行为是被动的。

2.）考虑可扩展性，猫的叫声可能引起其他联动效应。

代码：

要点：1. 联动效果，运行代码只要执行Cat.Cryed()方法。2. 对老鼠和主人进行抽象
评分标准: <1>.构造出Cat、Mouse、Master三个类，并能使程序运行(2分)
<2>从Mouse和Master中提取抽象（5分）
<3>联动效应，只要执行Cat.Cryed()就可以使老鼠逃跑，主人惊醒。(3分)

    public interface Observer
    {
        void Response();    //观察者的响应，如是老鼠见到猫的反映
    }
    public interface Subject
    {
        void AimAt(Observer obs); //针对哪些观察者，这里指猫的要扑捉的对象---老鼠
    }
    public class Mouse : Observer
    {
        private string name;
        public Mouse(string name, Subject subj)
        {
            this.name = name;
            subj.AimAt(this);
        }

        public void Response()
        {
            Console.WriteLine(name + " attempt to escape!");
        }
    }
    public class Master : Observer
    {
        public Master(Subject subj)
        {
            subj.AimAt(this);
        }

        public void Response()
        {
            Console.WriteLine("Host waken!");
        }
    }

    public class Cat : Subject
    {
        private ArrayList observers;
        public Cat()
        {
            this.observers = new ArrayList();
        }
        public void AimAt(Observer obs)
        {
            this.observers.Add(obs);
        }
        public void Cry()
        {
            Console.WriteLine("Cat cryed!");
            foreach (Observer obs in this.observers)
            {
                obs.Response();
            }
        }
    }
    class MainClass
    {
        static void Main(string[] args)
        {
            Cat cat = new Cat();
            Mouse mouse1 = new Mouse("mouse1", cat);
            Mouse mouse2 = new Mouse("mouse2", cat);
            Master master = new Master(cat);
            cat.Cry();
        }
    }

//---------------------------------------------------------------------------------------------

设计方法二: 使用event -- delegate设计..
    public delegate void SubEventHandler();
    public abstract class Subject
    {
        public event SubEventHandler SubEvent;
        protected void FireAway()
        {
            if (this.SubEvent != null)
                this.SubEvent();
        }
    }
    public class Cat : Subject
    {
        public void Cry()
        {
            Console.WriteLine("cat cryed.");
            this.FireAway();
        }
    }
    public abstract class Observer
    {
        public Observer(Subject sub)
        {
            sub.SubEvent += new SubEventHandler(Response);
        }
        public abstract void Response();
    }
    public class Mouse : Observer
    {
        private string name;
        public Mouse(string name, Subject sub) : base(sub)
        {
            this.name = name;
        }
        public override void Response()
        {
            Console.WriteLine(name + " attempt to escape!");
        }
    }
    public class Master : Observer
    {
        public Master(Subject sub) : base(sub){}
        public override void Response()
        {
            Console.WriteLine("host waken");
        }
    }
    class Class1
    {
        static void Main(string[] args)
        {
            Cat cat = new Cat();
            Mouse mouse1 = new Mouse("mouse1", cat);
            Mouse mouse2 = new Mouse("mouse2", cat);
            Master master = new Master(cat);
            cat.Cry();
        }

}