实验四_委托的实现与使用_().doc

验报告课程名称面向对象程序设计实验名称实验四、委托的实现与使用日期2015.4.28学生学号姓名班级实验目的：1理解委托和事件的概念2了解委托和事件在C#中的实现实验要求：1.认真阅读、掌握和本实验相关的教材内容。2.设计并编写代码完成题目要求的任务。3.撰写实验报告。实验内容与步骤：编写一个程序用来模拟考试流程，有一个老师类Teacher，学生类Student，老师引发考试事件，学生进行考试，学生答完题发出完成答题事件，老师收卷。1）创建一个名为DelegateEvent的控制台项目2）添加Student类，代码如下，要注意对toString方法的重载，Student类继承自Object类，Object类的默认toString方法返回的是命名空间和类名，Student类返回Student的成员变量name，这样使设计的类更可用。.NET Framework类库大多数类都对toString方法进行了重载using System;using System.Collections.Generic;using System.Text;namespace DelegateEvent /定义委托 public delegate void delegateFinishExam(DateTime FinishiTime, Student student); public class Student /用委托定义事件 public event delegateFinishExam FinishExam; private string name; public Student(string name) = name; /答题 public void Testing(DateTime BeginTime) Console.WriteLine(0t1t开始答题., name, BeginTime); /答题结束，引发考试完成事件 public void HandInPaper() Console.WriteLine(0答题完成, name); FinishExam(DateTime.Now, this); public override string ToString() return ; 3）添加Teacher类，代码如下：using System;using System.Collections.Generic;using System.Text;namespace DelegateEvent public delegate void DelegateStartExam(DateTime StartTime); public class Teacher public event DelegateStartExam StartExam; public void NotifyBeginExam() StartExam(DateTime.Now); /收卷 public void AcceptPaper(DateTime acceptTime, Student student) Console.WriteLine(收0的考卷, student.ToString()a; 4）改写Program.cs的代码如下：using System;using System.Collections.Generic;using System.Text;namespace DelegateEvent class Program static void Main(string args) Teacher teacher = new Teacher(); Student students = new Student5; int index = 0; studentsindex+ = new Student(张三); studentsindex+ = new Student(李四); studentsindex+ = new Student(王五); studentsindex+ = new Student(周六); studentsindex+ = new Student(冯七); foreach (Student tester in students) /事件 teacher.StartExam += new DelegateStartExam(tester.Testing); tester.FinishExam += new delegateFinishExam(teacher.AcceptPaper); /引发开始答卷事件 teacher.NotifyBeginExam(); /引发完成答卷事件 students1.HandInPaper(); 5）按Ctr