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();

        }

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; }

        }

        /// <summary>

        /// 接收arraylist，排序后，返回arraylist

        /// </summary>

        /// <param name="arr">存放了student类对象的arraylist</param>

        /// <returns>返回排序后的集合</returns>

        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;

        }

    }

}