C# 接口

■接口：使用關鍵字interface，只是定義一系列的行爲類型，不提供任何實現
interface IMovable{
    float speed{get;}
    float maxSpeed{get;set;}
    void Run()；
    void Walk();
    void Fly();
}
■接口的實現，通過冒號來實現

<!--<br /> <br /> Code highlighting produced by Actipro CodeHighlighter (freeware)<br /> http://www.CodeHighlighter.com/<br /> <br /> -->using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace useInterface
{
    interface IMovable {
        float Speed{get;}
        float MaxSpeed { get; set; }
        void Run();
        void Walk();
        void Fly();
    }
    class Dog : IMovable {
        public float Speed {
            get {
                return 10.5f;
            }
        }
        private float _MaxSpeed;
        public float MaxSpeed{
            get { return this._MaxSpeed; }
            set { this._MaxSpeed = value; }
        }
        public void Run() {
            System.Console.WriteLine("Dog is running");
        }
        public void Walk()
        {
            System.Console.WriteLine("Dog is walking");
        }
        public void Fly()
        {
            System.Console.WriteLine("Dog can't fly");
        }

    }
    class Person : IMovable
    {
        public float Speed
        {
            get
            {
                return 20.5f;
            }
        }
        private float _MaxSpeed;
        public float MaxSpeed
        {
            get { return this._MaxSpeed; }
            set { this._MaxSpeed = value; }
        }
        public void Run()
        {
            System.Console.WriteLine("Person is running");
        }
        public void Walk()
        {
            System.Console.WriteLine("Person is walking");
        }
        public void Fly()
        {
            System.Console.WriteLine("Person flies with a plane");
        }

    }
    class Program
    {
        static void SthMove(IMovable mov) {
            string type = mov.GetType().Name;
            System.Console.WriteLine("This is a {0} ",type);
            System.Console.WriteLine("{0}.Speed={1}",type,mov.Speed);
            System.Console.WriteLine("{0}.MaxSpeed={1}", type, mov.MaxSpeed);
            mov.Walk();
            mov.Run();
            mov.Fly();
        }
        static void Main(string[] args)
        {
            Person aPerson = new Person();
            aPerson.MaxSpeed = 50;
            SthMove(aPerson);
            IMovable mov = new Dog();
            mov.MaxSpeed = 20;
            SthMove(mov);
            System.Console.ReadLine();
        }
    }
}

結果：
This is a Person
Person.Speed=20.5
Person.MaxSpeed=50
Person is walking
Person is running
Person flies with a plane
This is a Dog
Dog.Speed=10.5
Dog.MaxSpeed=20
Dog is walking
Dog is running
Dog can't fly

一個類可以實現多個接口。如有兩個接口IMovable，ISpeakable，定義一個Person類來實現這兩個接口
class Person:IMovable,ISpeakable