自己的第一个完整程序-控制台计算器

/**//*------------------------------------------------
    程序名:counter.cs
    程序功能:计算器
    制作者:ZHOULONG
    代码行数:96行
    制作时间:2007-10-24
---------------------------------------------------*/    
using System;

namespace Test
{
    class Test
    {
        static void Main()
        {
            int count = 0;
            while (count < 5) //设置循环5次
                {
            Console.Clear();
            int top = 0;
            Console.Clear();
            //绘制界面头部
            string title = "四 则 运 算 计 算 器 V1.2";
            Console.WriteLine("*".PadLeft(80, '*'));
            Console.SetCursorPosition(30, ++top);
            Console.WriteLine(title);
            Console.SetCursorPosition(42, ++top);
            Console.WriteLine("制作人：ZHOULONG");
            Console.WriteLine("*".PadLeft(80, '*'));
        Console.WriteLine("                              本程序还可以用{0}次\n",5-count);        
                    try //如果用户输入有错，提示！
                    {                
        Console.WriteLine("                       请问你要做什么算法:\n");
        Console.WriteLine("                                1 - 加 法 运 算");
        Console.WriteLine("                                2 - 减 法 运 算");
        Console.WriteLine("                                3 - 乘 法 运 算");
        Console.WriteLine("                                4 - 除 法 运 算\n");
        Console.Write("                                                  请 选 择：");
        int x = int.Parse(Console.ReadLine());
            switch (x)   // 多选择控制语句。
            {
            case 1:    // 用case来定义每一个选择项。
                Counter1();
            break;
            case 2:
                Counter2();
            break;
            case 3:
                Counter3();
            break;
            case 4:
                Counter4();
            break;
            default:
            Console.WriteLine("出错，只能输入： 1, 2，3 or 4.");
            break;
            }
            Console.WriteLine("感谢你使用本程序！\n按Enter继续计算！");
            Console.ReadLine();
                    }
                    catch
                    {
                    Console.WriteLine("只能输入数字，谢谢！按Enter重新启动本程序！");
                    Console.ReadLine();
                    }
                    Console.Clear(); //  清屏操作。
                    count++;
                }
        }
        
        private static void Counter1()
        {
               Console.WriteLine("请输入加数：");
            double a1 = double.Parse(Console.ReadLine());
            Console.WriteLine("请输入另一个加数：");
            double a2 = double.Parse(Console.ReadLine());
            double aa = a1 + a2;
            Console.WriteLine("结果为：\n\n{0} + {1} = {2}\n",a1,a2,aa);
        }
        private static void Counter2()
        {
            Console.WriteLine("请输入被减数：");
            double m1 = double.Parse(Console.ReadLine());
            Console.WriteLine("请输入另一个减数：");
            double m2 = double.Parse(Console.ReadLine());
            double mm = m1 - m2;
            Console.WriteLine("结果为：\n\n{0} - {1} = {2}\n",m1,m2,mm);
        }
        private static void Counter3()
        {
            Console.WriteLine("请输入乘数：");
            double r1 = double.Parse(Console.ReadLine());
            Console.WriteLine("请输入另一个乘数：");
            double r2 = double.Parse(Console.ReadLine());
            double rr = r1 * r2;         
            Console.WriteLine("结果为：\n\n{0} * {1} = {2}\n",r1,r2,rr);
        }
        private static void Counter4()
        {
            Console.WriteLine("请输入被除数：");
            double g1 = double.Parse(Console.ReadLine());
            Console.WriteLine("请输入除数：");
            double g2 = double.Parse(Console.ReadLine());
            double gg = g1 / g2;        
            Console.WriteLine("结果为：\n\n{0} / {1} = {2}\n",g1,g2,gg);
        }
    }
}