[C#]练习了下数组和类，C++ 基础还算可以，不是很吃力

using System;

namespace _02
{
    class SortNum  //输入几个数、排序、输出
    {
        private int[] iNum;

        public SortNum()
        {
            Init();
            InputValue();
        }

        private void Init()  //读入数字总数并分配空间
        {
            Console.WriteLine("请输入数字的总数:");
            try
            {
                iNum = new int[Int16.Parse(Console.ReadLine())];
            }
            catch
            {
                Console.WriteLine("您输入的不是有效的数字。");
                Init();
            }
        }

        private void InputValue()  //输入数字
        {   
            for(int i = 0;i < iNum.Length; i++)
            {
                Console.WriteLine("请输入第 {0} 个数字:", i + 1);
                try
                {
                    iNum[i] = Int16.Parse(Console.ReadLine());
                }
                catch
                {
                    Console.WriteLine("您输入的不是有效的数字。");
                    i--;
                }
            }
            Console.WriteLine("输入结束。");
        }

        public void Sort(bool inverse)
        //选择法排序, 若 inverse 为真则从大到小排序, 否则从小到大排序
        {
            int i, j, temp;

            for (i = 0; i < iNum.Length; i++)
            {
                for (j = i + 1; j < iNum.Length; j++)
                {
                    if (inverse)
                    {
                        if (iNum[i] < iNum[j])
                        {
                            temp = iNum[i];
                            iNum[i] = iNum[j];
                            iNum[j] = temp;
                        }
                    }
                    else
                    {
                        if (iNum[i] > iNum[j])
                        {
                            temp = iNum[i];
                            iNum[i] = iNum[j];
                            iNum[j] = temp;
                        }
                    }
                }
            }
        }

        public void Sort()  //从小到大
        {
            Sort(false);
        }

        public void Print()  //输出
        {
            foreach (int num in iNum)
            {
                Console.Write("{0, 3}", num);
            }
            Console.Write("/n");
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            do
            {
                SortNum a = new SortNum();

                Console.WriteLine("您输入的数字是:");
                a.Print();
                a.Sort();
                Console.WriteLine("从小到大排序后是:");
                a.Print();
                a.Sort(true);
                Console.WriteLine("从大到小排序后是:");
                a.Print();

                Console.Write("按 ESC 退出, 其他任意键继续.../n/n");
            }
            while (Console.ReadKey(true).Key != ConsoleKey.Escape);
        }
    }
}

/*
 * 学习手记
 * 
 * Console.ReadLine() 从标准输入设备读入一行字符串
 * Int16.Parse() 将字符串转换为 Int16 类型数值
 * try...catch... 出错控制，感觉用起来还挺方便
 * 跟 C/C++ 的一个重大区别是，定义数组、类其实都相当于定义指针
 * 并没有分配空间，还要用 new 去分配空间
 * 据说不用 delete 它会自动回收空间
 * 那么析构函数似乎用不太着了
 * 居然不支持默认参数，只好用重载
 * Console.ReadKey() 返回一个 ConsoleKeyInfo 对象, 其 Key 成员表示相应的键
 * 
 * 2005-06-09
 */


（原发表于 CSDN：https://blog.csdn.net/cnStreamlet/article/details/1646808）