抽象类和接口的应用

1. 先定义一个基类 “人”

    /// <summary>
    /// 定义一个基类human
    /// 有姓名，性别，年龄等属性，吃饭睡觉等行为
    /// 1. 抽象方法必须放在抽象类中
    /// 2. 抽象类可以包含实例方法、字段、委托、别的类、事件、属性
    /// 3. 抽象类不能被实例化
    /// 4. is a
    /// </summary>
    public abstract class BaseHuman
    {
        public string Name { set; get; }
        public bool Sex { set; get; }
        public int Age { set; get; }
        public void Eat()
        {
            Console.WriteLine("{0}  have the eat action", this.Name );
        }
        public void Sleep()
        {
            Console.WriteLine("{0} have the sleep action", this.Name  );
        }
        public abstract void Career(); //因为职业可能不同，所以这里定义了抽象方法，那么类就必须定义成抽象类
    }

2. 定义两个类“程序员”和“翻译官”

    /// <summary>
    /// 单继承，多接口
    /// </summary>
    public class Programmer:BaseHuman,Iknowledge
    {
        public override void Career()
        {
            Console.WriteLine("{0} is a programmer", this.Name);
        }
        public void Knowledge()
        {
            Console.WriteLine("{0} knows C#, SQL,Html", this.Name);
        }
    }

    class Translator:BaseHuman,Iknowledge 
    {
        public override void Career()
        {
            Console.WriteLine("{0} is a  translator", this.Name );
        }
        public void Knowledge()
        {
            Console.WriteLine ("{0} knows Englsh, Franch",this.Name );
        }
    }

3. 定义一个接口

   /// <summary>
    /// 接口只能包含 方法、属性和事件
    /// 不能包含字段，实例方法，委托和别的类
    /// can do
    /// </summary>
    public interface Iknowledge
    {
        void Knowledge();
    }