计算从哪天起应该购买预售火车票.cs

代码直接CSC编译即可。

计算从哪天起应该购买预售火车票.cs

using System;
using System.Diagnostics;
using System.IO;

class Program
{
    static ConsoleColor DefaultForegroundColor = Console.ForegroundColor; //保留Console前景色
    
    static int Main(params string[] args)
    {
        int days = 0; //预售天数
        if (args.Length>0)
        {
            if(!int.TryParse(args[0], out days))
            {
                ShowHelpAndExit(1); //第一个参数错误
            }
            else if(args.Length>1)
            {
                DateTime argsDate; //出行日期
                if(args[1].Trim().Equals("now",StringComparison.OrdinalIgnoreCase))
                {
                    argsDate = DateTime.Now.AddDays(days - 1); //出行日期为now的话，计算出今天可预订的出行日期
                }
                else if(!DateTime.TryParse(args[1], out argsDate))
                {
                    ShowHelpAndExit(2); //第二个参数错误
                }                
                Console.WriteLine("\r\n * 火车票预售期为：{0}天\r\n\r\n出行日期：{1}",days, FormatDate(argsDate));
                OutputBookingDay(days, argsDate); //输出预售日期
                var paused = true;
                if(args.Length>2)
                {
                    if(args[2].Trim().Equals("nopause",StringComparison.OrdinalIgnoreCase))
                    {
                        paused = false; //第三个参数为 nopause 则不暂停直接退出，用于配合命令提示符
                    }
                }
                if(paused)
                {
                    Console.Write("\r\n按任意键退出...");
                    Console.ReadKey(true);
                }
                Environment.Exit(0); //正常退出
            }
        }
        else
        {
            Console.WriteLine("计算从哪天起应该购买预售火车票"); //未带参数，输出标题
            Console.WriteLine();
        }
        if(days <= 0)
        {
            Console.Write("火车票预售期（缺省为60天）：");
            var input=Console.ReadLine().Trim();  //手动输入预售期
            inputToExit(input);
            if (!int.TryParse(input, out days)||days<=0)
            {
                days = 60; //输入错误，预售期设置为60天
                ConsoleCursorRelativeLine(-1); //光标移动到上一行行首。
                var point = ConsoleCursorGetCurrentPosition();
                if(point!=null)
                {
                    ConsoleCursorFillLines(point.Value.Top,point.Value.Top, ' '); //清除光标所在行的显示字符（用空格填充）
                    Console.Write("火车票预售期（缺省为60天）：{0}\r\n", days);
                }
            }
        }
        Console.WriteLine("\r\n * 火车票预售期为：{0}天",days);
        Console.WriteLine(" * 今天可以预定 {0} 的火车票", FormatDate(DateTime.Now.AddDays(days - 1)));
        Console.WriteLine(" * 输入\"exit\"可退出程序，输入\"g\"打开12306订票网站。\r\n");
        while(true)
        {
            Console.Write("出行日期：");  //输入出行日期
            var input = Console.ReadLine().Trim();
            inputToExit(input);  //若输入exit则退出
            if(input.Equals("g",StringComparison.OrdinalIgnoreCase))
            {
                const string web = "http://www.12306.cn";
                Process.Start(web); //输入g打开12306网站
                Console.WriteLine("正在打开 {0} ", web);
            }
            else
            {
                DateTime dest;
                if(DateTime.TryParse(input, out dest))
                {
                    ConsoleCursorRelativeLine(-1);
                    var point = ConsoleCursorGetCurrentPosition();
                    if(point!=null)
                    {
                        ConsoleCursorFillLines(point.Value.Top,point.Value.Top, ' '); //清除前一行显示字符
                        Console.WriteLine("出行日期：{0}",FormatDate(dest)); //更新输出日期
                    }
                    OutputBookingDay(days, dest);
                }
                else
                {
                    Console.ForegroundColor = ConsoleColor.Red;
                    Console.WriteLine("输入错误"); //显示输出错误
                    Console.ForegroundColor = DefaultForegroundColor;
                    ConsoleCursorRelativeLine(-3); //光标向上移动3行
                    var point = ConsoleCursorGetCurrentPosition();
                    if(point!=null)
                    {
                        ConsoleCursorFillLines(point.Value.Top,point.Value.Top+1, ' ');
                    }
                }
            }
            Console.WriteLine();
        }
    }
    
    static void inputToExit(string input)
    {
        if(input.Equals("exit", StringComparison.OrdinalIgnoreCase))
        {
             Environment.Exit(0); //用户退出
        }
    }
    
    static void ShowHelp()
    {
        //帮助提示
        var appname = Path.GetFileName(Environment.GetCommandLineArgs()[0]);
        Console.WriteLine(" * 参数格式：");
        Console.WriteLine("   {0} <火车票预售期>", appname);
        Console.WriteLine("   {0} <火车票预售期> <出行日期> [nopause]", appname);
        Console.WriteLine("   {0} <火车票预售期> now [nopause]", appname);
        Console.WriteLine("\r\n * 例子：预售期60天，查看今天可以预定哪天火车票");
        Console.WriteLine("   {0} 60 now", appname);
        Console.WriteLine("\r\n * 批处理：");
        Console.WriteLine("   {0} 60 now nopause|Find \"出行日期：\"", appname);
        Console.WriteLine();
    }
    
    static void ShowHelpAndExit(int exitcode)
    {
        ShowHelp(); //显示帮助提示然后按任意键退出
        Console.Write("按任意键退出...");
        Console.ReadKey(true);
        Environment.Exit(exitcode); //返回错误码(errorlevel)
    }
    
    static string FormatDate(DateTime date)
    {
        ConsoleColor? cc;
        return FormatDate(date, out cc); //格式化日期
    }
    
    static string[] dayOfWeek = new []{ "周日", "周一", "周二", "周三", "周四", "周五", "周六" };
    static string FormatDate(DateTime date, out ConsoleColor? consoleColor)
    {        
        var d = (date.Date - DateTime.Now.Date).Days;
        string tip;
        switch (d)
        {
            case -2:
                tip = "（前天）";
                break;
            case -1:
                tip = "（昨天）";
                break;
            case 0:
                tip = "（今天）";
                break;
            case 1:
                tip = "（明天）";
                break;
            case 2:
                tip = "（后天）";
                break;
            default:
                tip = string.Format("（{0}）",dayOfWeek[(int)date.DayOfWeek]);
                break;
        }
        
        if (d>=0)
        {
            consoleColor = ConsoleColor.Green;  //返回建议颜色，下同
        }
        else
        {
            consoleColor = ConsoleColor.Yellow;
        }
        
        return string.Format("{0:yyyy-M-d}{1}", date, tip);
    }
    
    static void OutputBookingDay(int days, DateTime destDate)
    {
        var date = destDate.AddDays(-days + 1);
        ConsoleColor? cc;
        var formattedDest = FormatDate(date, out cc);
        Console.ForegroundColor = DefaultForegroundColor;
        Console.Write("预售日期："); //用缺省前景色显示“预售日期：”这几个字
        if(cc.HasValue)
        {
            Console.ForegroundColor = cc.Value; //更换前景色
        }
        Console.WriteLine(formattedDest); //按格式输出预售日期
        Console.ForegroundColor = DefaultForegroundColor; //还原缺省前景色
    }
    
    static bool ConsoleCursorRelativeLine(int rows)
    {
        //将ConsoleCursor操作封装成方法，加入try语句，防止在非控制台下输出造成异常，下同
        try
        {
            var t = Console.CursorTop + rows; //相对行号
            Console.SetCursorPosition(0, t); //移动光标到相对行
            return true; //成功
        }
        catch
        {
        }
        return false; //失败
    }
    
    static bool ConsoleCursorFillLines(int startLine, int endLine, char @char)
    {
        var d = endLine - startLine + 1;
        if (d>0)
        {
            try 
            {
                var point = ConsoleCursorGetCurrentPosition().Value;            
                Console.SetCursorPosition(0, startLine); //光标移动到起始行
                Console.Write(new string(@char,Console.BufferWidth * d)); //用字符填满指定行数(d)
                Console.SetCursorPosition(point.Left, point.Top); //返回光标原来的位置
                return true; //成功
            }
            catch
            {
            }
        }
        return false; //失败
    }
    
    static Point? ConsoleCursorGetCurrentPosition()
    {
        try
        {
            return new Point(Console.CursorLeft, Console.CursorTop); //返回光标位置
        }
        catch
        {
        }
        return null; //失败
    }
    
    struct Point
    {
        public int Left;
        public int Top;
        
        public Point(int left, int top)
        {
            Left = left;
            Top = top;
        }
    }
}