Question

当我使用调试器逐步执行程序时，它可以正常工作并显示正确的结果。但是，当我运行程序时，它会为homeTeamRuns和awayTeamRun显示一些极高的数字。我似乎无法弄清楚问题。

class BallGame
    {
        //Fields
        private string output = ""; 

        int outs = 0;
        int runs = 0;

        int homeTeamRuns = 0;
        int awayTeamRuns = 0;

        bool homeTeam = false;
        bool awayTeam = false;

        int[] innings = new int[12]; //Innings 

        //Properties
         public string Output
         {
             get
             {
                 return output;
             }
             set
             {
                 output = value;
             }
         }

        //Game Simulator
        public void playBall()
        {

            int[] play = new int[4];  //Bases



            for(int i = 1; i <= 2; i++)
            {
                homeTeam = false;
                awayTeam = false;



                if(i%2 == 0)
                    homeTeam = true;
                else 
                    awayTeam = true;

            //Half Inning
            while (outs < 3)
            {

                bool yourOut = false, single = false, double1 = false, triple = false, homerun = false;

                Random rnd1 = new Random();
                int randomNum = rnd1.Next(1, 101);

                //
                if (randomNum >= 1 && randomNum <= 50) //50% chance
                    yourOut = true;
                else if (randomNum > 50 && randomNum <= 60) //10% chance
                    single = true;
                else if (randomNum > 60 && randomNum <= 92) //42% chance
                    double1 = true;
                else if (randomNum > 92 && randomNum <= 97) //5% chance
                    triple = true;
                else if (randomNum > 97 && randomNum <= 100) //%3 chance
                    homerun = true;


                if (yourOut == true)
                {
                    outs++;
                }
                else if (single == true)
                {
                    Shift(play);
                    runScored(play);

                    play[0] = 1;
                }
                else if (double1 == true)
                {
                    Shift(play);
                    runScored(play);

                    Shift(play);
                    runScored(play);

                    play[1] = 1;
                }
                else if (triple == true)
                {
                    Shift(play);
                    runScored(play);

                    Shift(play);
                    runScored(play);

                    Shift(play);
                    runScored(play);

                    play[2] = 1;
                }
                else if (homerun == true)
                {
                    Shift(play);
                    runScored(play);

                    Shift(play);
                    runScored(play);

                    Shift(play);
                    runScored(play);

                    Shift(play);
                    runScored(play);

                    play[3] = 1;
                }


                play[3] = 0;

                if (outs == 3)
                {
                    play[0] = 0;
                    play[1] = 0;
                    play[2] = 0;
                    play[3] = 0;
                }
            }

            outs = 0;

            }
            output = "Home Team Runs: " + homeTeamRuns + " Away Team Runs: " + awayTeamRuns;

         }

        //Shift Array
        public int[] Shift(int[] array)
        {
            for (int i = array.Length -1; i >= 1; i--)
            {
                array[i] = array[i - 1];
            }
            array[0] = 0;

            return array;
        }

        public void runScored(int[] array)
        {
            if(array[3] == 1)
            {
                if(awayTeam == true)
                    awayTeamRuns++;
                else if(homeTeam == true)
                    homeTeamRuns++;
            }
        }


    }

Answer 1

您正在循环的每次迭代中创建Random类的新实例。您正在使用的构造函数的documentation表示：

使用与时间相关的默认种子值初始化Random类的新实例。

由于循环在您不进行调试时执行得非常快，因此最终会在多次迭代中使用相同的种子，因此对Next的调用每次都返回相同的值。如果该值碰巧是一个会增加分数的值，那么分数将在循环的多次迭代中递增。

移动线

Random rnd1 = new Random();

在您的for循环上方

将构建一个Random实例，然后为每次调用Next创建一个新的随机数。

在调试器中运行时无法重现这一点，因为在创建新Random实例时时钟已经移动，因此种子已更改。

有关Random实例返回相同值的更多信息，请参阅this StackOverflow帖子。此外，Jon Skeet在使用Random类时有blog post覆盖陷阱，这非常值得一读。

方法显示不正确的结果

1 个答案: