<C#任务导引教程>练习十

/*83,使用接口完成多继承问题 简化版*/
using System;
interface ITeacher
{
    string Name
    {
        get;
        set;
    }
    int Age
    {
        get;
        set;
    }
    string Title
    {
        get;
        set;
    }
}
interface IStudent
{
    string Sex
    {
        get;
        set;
    }
    double Score
    {
        get;
        set;
    }
}
class Graduate : ITeacher, IStudent
{
    public Graduate(string n, int a, string t, string s, double sco, float w)
    {
        Name = n;
        Age = a;
        Title = t;
        Sex = s;
        Score = sco;
        wage = w;
    }
    string name = " ";
    public string Name
    {
        get { return name; }
        set { name = value; }
    }
    int age = 0;
    public int Age
    {
        get { return age; }
        set { age = value; }
    }
    string title = " ";
    public string Title
    {
        get { return title; }
        set { title = value; }
    }
    string sex = " ";
    public string Sex
    {
        get { return sex; }
        set { sex = value; }
    }
    double score = 0.0;
    public double Score
    {
        get { return score; }
        set { score = value; }
    }
    //public void Set(double w)//可要可不要
    //{
    //    wage = w;
    //}
    public void show()
    {
        Console.WriteLine(" 基本信息: ");
        Console.WriteLine("  姓名：{0}", name);
        Console.WriteLine("  性别：{0}", sex);
        Console.WriteLine("  年龄：{0}", age);
        Console.WriteLine("  职称：{0}", title);
        Console.WriteLine("  工资：{0}", wage);
        Console.WriteLine("  成绩：{0}", score);
    }
    private double wage;
}
class Program
{
    static void Main()
    {
        Graduate grad = new Graduate("王莉", 24, "助教", "女", 89.5, 1234.50f);
        grad.show();
    }
}
//84，若程序设计语言不支持多态性，不能成为面向对象语言
using System;
class Unstudent
{
    protected int no;
    protected string name;
    protected int fee1, fee2, fee3, fee4, fee;
    public void calfee()
    {
        Console.Write("  学号:");
        no = Convert.ToInt32(Console.ReadLine());
        Console.Write("  姓名:");
        name = Console.ReadLine();
        fee1 = 4800;
        fee2 = 800;
        fee3 = 400;
        fee4 = 200;
        fee = fee1 + fee2 + fee3 + fee4;
    }
    public void disp()
    {
        Console.WriteLine("  学 费:{0}",fee1);
        Console.WriteLine( " 住宿费:{0}",fee2);
        Console.WriteLine("  书本费:{0}",fee3);
        Console.WriteLine("  其他费:{0}",fee4);
        Console.WriteLine("  总费用:{0}",fee);
    }
    public void fn()
    {
        calfee();
        disp();
    }
}

class Graduate : Unstudent
{
    public new void calfee()
    {
        Console.Write("  学号:");
        no = Convert.ToInt32(Console.ReadLine());
        Console.Write("  姓名:");
        name = Console.ReadLine();
        fee1 = 1100;
        fee2 = 600;
        fee3 = 200;
        fee = fee1 + fee2 + fee3;
    }
    public new void disp()
    {
        Console.WriteLine(" 住宿费:{0}", fee1);
        Console.WriteLine("  书本费:{0}", fee2);
        Console.WriteLine("  其他费:{0}", fee3);
        Console.WriteLine("  总费用:{0}", fee);
    }
}
class Program
{
    static void Main()
    {
        Unstudent s1 = new Unstudent();
        Graduate s2 = new Graduate();
        Console.WriteLine("本科生收费");
        s1.fn();
        Console.WriteLine("研究生收费");
        s2.fn();
    }
}
//85，虚方法就是允许被其他派生类重新定义的方法，在方法声明时需要使用virtual修饰符
//virtual修饰符不能与static,cabstract,override修饰符同时使用，并且虚方法是从基类继承来的公有成员，因此virtual修饰符也不能与private修饰符同时使用
using System;
class A
{
    public void F()
    {
        Console.WriteLine("A.F");
    }
    public virtual void G()
    {
        Console.WriteLine("A.G");
    }
}
class B : A
{
    public new void F()
    {
        Console.WriteLine("B.F");
    }
    public override void G()
    {
        Console.WriteLine("B.G");
    }
}
class Program
{
    static void Main()
    {
        B b = new B();
        A a = b;
        a.F();
        b.F();
        a.G();
        b.G();
    }
}

/*86，重写方法，使用了override修饰符，表明该方法是重写方法，主要用来使用相同的签名重写继承的虚方法，虚方法主要用来引入新方法，而重写方法则使
从基类继承而来的虚方法专门化从而提供虚方法的具体实现。重写与重载是不同的，重写是指在派生类中重新写过基类的虚方法，而重载则是指编写一个与已有方法同名的但参数
 列表不同的方法。另外，override修饰符不能与new static virtual修饰符同时使用，重写方法只能用于重写基类中的虚方法，不能用来单独声明方法*/
using System;
class Unstudent
{
    protected int no;
    protected string name;
    protected int fee1, fee2, fee3, fee4, fee;
    public void calfee()
    {
        Console.Write("  学号:");
        no = Convert.ToInt32(Console.ReadLine());
        Console.Write("  姓名:");
        name = Console.ReadLine();
        fee1 = 4800;
        fee2 = 800;
        fee3 = 400;
        fee4 = 200;
        fee = fee1 + fee2 + fee3 + fee4;
    }
    public void disp()
    {
        Console.WriteLine("  学 费:{0}",fee1);
        Console.WriteLine( " 住宿费:{0}",fee2);
        Console.WriteLine("  书本费:{0}",fee3);
        Console.WriteLine("  其他费:{0}",fee4);
        Console.WriteLine("  总费用:{0}",fee);
    }
    public virtual void fn()
    {
        calfee();
        disp();
    }
}

class Graduate : Unstudent
{
    public new void calfee()
    {
        Console.Write("  学号:");
        no = Convert.ToInt32(Console.ReadLine());
        Console.Write("  姓名:");
        name = Console.ReadLine();
        fee1 = 1100;
        fee2 = 600;
        fee3 = 200;
        fee = fee1 + fee2 + fee3;
    }
    public new void disp()
    {
        Console.WriteLine(" 住宿费:{0}", fee1);
        Console.WriteLine("  书本费:{0}", fee2);
        Console.WriteLine("  其他费:{0}", fee3);
        Console.WriteLine("  总费用:{0}", fee);
    }
    public override void fn()
    {
        calfee();
        disp();
    }
}
class Program
{
    static void Main()
    {
        Unstudent s1 = new Unstudent();
        Graduate s2 = new Graduate();
        Console.WriteLine("本科生收费");
        s1.fn();
        Console.WriteLine("研究生收费");
        s2.fn();
    }
}
/*87,在C#中virtual修饰符必须与override修饰符配合使用，因此在派生类中fn()要显式表示，virtual修饰符放在基类中，指明该函数成员为虚方法（函数），
 override修饰符放在派生类中，以体现它是重写方法（函数。用抽象类编写程序，分别求矩形面积和圆的面积）*/
using System;
public abstract class Shapes
{
    public abstract void disp();
}
class Rectangle : Shapes
{
    protected int x, y;
    public void setvalue(int d, int w)
    {
        x = d;
        y = w;
    }
    public override void disp()
    {
        Console.WriteLine("矩形面积:{0}", x * y);
    }
}
class Circle : Shapes
{
    protected int x;
    public void setvalue(int d)
    {
        x = d;
    }
    public override void disp( )
    {
        Console.WriteLine("圆面积:{0}", 3.14159 * x * x);
    }
}
class Program
{
    static void Main()
    {
        Rectangle r1 = new Rectangle();
        Circle c1 = new Circle();
        r1.setvalue(10, 5);
        r1.disp();
        c1.setvalue(10);
        c1.disp();
    }
}
//88,委托是C#中的一种引用类型，通过委托实例调用静态方法和实例方法示例
using System;
delegate void D(int n);
class C
{
    public static void M0(int i)
    {
        Console.WriteLine("调用静态方法M0!={0}", i);
    }
    public static void M1(int i)
    {
        Console.WriteLine("调用静态方法M1!={0}", i);
    }
    public void M2(int i)//无static
    {
        Console.WriteLine("调用静态方法M2!={0}", i);
    }
}
class Program
{
    static void Main()
    {
        D cd0 = new D(C.M0);
        cd0(1);
        D cd1 = new D(C.M1);
        cd1(2);
        C t = new C( );
        D cd2 = new D(t.M2);
        cd2(3);
        D cd3 = new D(cd2);
        cd3(4);
    }
}