namespace fengzhuang{    class Class2    {        private string _Name;        private string _Code;        public string _Sex;        public Class2()//构造函数        {            _Sex = "男";//每次初始化都会默认_Sex的值为“男”            Console.WriteLine("构造函数");        }        public string nv()//函数         {            _Sex = "女";            return _Sex;        }    }}

 

static void Main(string[] args)        {            Class2 op=new Class2();//本身就存在的，只要初始化一下类，便会调用函数，            Console.WriteLine(op._Sex);            op.nv();//调用函数，            Console.WriteLine(op._Sex);            Console.WriteLine();            Console.ReadLine();        }

 

习题：

using System;using System.Collections;using System.Collections.Generic;using System.Linq;using System.Text;namespace xueshengxuanke{    class Program    {        static void Main(string[] args)        {            Console.WriteLine("请输入学生人数：");            int n = int.Parse(Console.ReadLine());            Console.WriteLine("请输入学生学号、姓名、分数");            ArrayList arr = new ArrayList();            for (int i = 0; i < n; i++)            {                student s = new student();                Console.Write("学号：");                s.Code = int.Parse(Console.ReadLine());                Console.Write("姓名：");                s.Name = Console.ReadLine();                Console.Write("分数：");                s.Score = decimal.Parse(Console.ReadLine());                arr.Add(s);            }            decimal sum = 0;            for (int i = 0; i < n; i++)            {                student avgs = (student)arr[i];                sum += avgs.Score;            }            ArrayList newarr = new student().Maopao(arr);            student ss1 = (student)newarr[0];            Console.WriteLine("姓名：{0}最高分为：{1}", ss1.Name, ss1.Score);            int x = n - 1;            student ss2 = (student)newarr[x];            Console.WriteLine("姓名：{0}最低分为：{1}", ss2.Name, ss2.Score);            Console.WriteLine("平均分：{0}", sum / n);            for (int i = 0; i < n; i++)            {                student avgs = (student)newarr[i];                Console.WriteLine("学生名次为：***********************************");                Console.WriteLine("学号         姓名           分数                 名次");                Console.WriteLine("{0}         {1}           {2}                 {3}", avgs.Code, avgs.Name, avgs.Score, i + 1);            }            Console.ReadLine();        }    }}

 

using System;using System.Collections;using System.Collections.Generic;using System.Linq;using System.Text;namespace xueshengxuanke{    class student    {        private int _Code;        public int Code        {            get { return _Code; }            set { _Code = value; }        }        private string _Name;        public string Name        {            get { return _Name; }            set { _Name = value; }        }        private decimal _Score;        public decimal Score        {            get { return _Score; }            set { _Score = value; }        }        /// 
        /// 接收arraylist，排序后，返回arraylist        /// 
        /// 存放了student类对象的arraylist        /// 
     
      返回排序后的集合
             public ArrayList Maopao(ArrayList arr)        {            int n = arr.Count;            for (int i = 0; i < n; i++)            {                for (int j = i; j < n; j++)                {                    student s1 = (student)arr[i];                    student s2 = (student)arr[j];                    if (s1.Score < s2.Score)                    {                        student zhong = new student();                        zhong = s1;                        arr[i] = s2;                        arr[j] = zhong;                    }                }            }            return arr;        }    }}