第二个用户输入的验证无法正常工作，我被告知我有很多不必要的编码

Question

这是我学习计算机编程课程的第一年，我当前的任务之一是创建一个可行的石头剪刀布游戏。

我已经完成了大部分工作，但我的老师说我有很多不必要的代码，但没有真正告诉我它们是什么。我希望尽可能地简化流程，因为我不仅仅满足于任何有效的方法。

同样，用户输入的第二次验证（用户做出选择，程序运行并显示谁获胜，然后被要求再次做出选择）不像第一次那样工作，我无法弄清楚出了什么问题。过去两周我一直在研究这个问题，但无法弄清楚，因此非常感谢您的帮助。

我的代码如下：

namespace Assignment04
{
class Program
{
    static void Main(string[] args)
    {
        // Declare variables
        int gamesPlayed = 0, userWins = 0, computerWins = 0, draws = 0, userSelection, computerSelection;
        bool inputIsValid = false;
        // Prompt user
        Console.WriteLine("Welcome to the Rock, Paper, Scissors game!");
        Console.WriteLine("1 - Rock");
        Console.WriteLine("2 - Paper");
        Console.WriteLine("3 - Scissors");
        Console.WriteLine("4 - Quit program and view record");
        // Create a loop to validate user's selection
            do
            {
                Console.Write("Please make a selection: ");
                // loop and test using TryParse()
                while (!int.TryParse(Console.ReadLine(), out userSelection))
                {
                    // invalid data type
                    Console.WriteLine("Invalid input.");
                    Console.Write("Please make a selection: ");
                }
                // test if input is within acceptable range
                if (userSelection >= 1 && userSelection <= 4)
                {
                    inputIsValid = true;
                }
                else
                {
                    // valid integer, but out of acceptable range
                    Console.WriteLine("Number out of range.");
                }
            } while (!inputIsValid);
            // Display user's choice
            while (userSelection >= 1 && userSelection <= 3)
            {
                if (userSelection == 1)
                {
                    Console.WriteLine("\nYou have selected Rock");
                    gamesPlayed = gamesPlayed + 1;
                }
                else if (userSelection == 2)
                {
                    Console.WriteLine("\nYou have selected Paper");
                    gamesPlayed = gamesPlayed + 1;
                }
                else if (userSelection == 3)
                {
                    Console.WriteLine("\nYou have selected Scissors");
                    gamesPlayed = gamesPlayed + 1;
                }
                // Generate computer's choice
                Random randomNumber = new Random();
                computerSelection = randomNumber.Next(1, 4);
                // Display computer's choice
                if (computerSelection == 1)
                {
                    Console.WriteLine("Computer has chosen Rock");
                }
                else if (computerSelection == 2)
                {
                    Console.WriteLine("Computer has chosen Paper");
                }
                else if (computerSelection == 3)
                {
                    Console.WriteLine("Computer has chosen Scissors");
                }
                // Calculate and display who wins
                if (userSelection == computerSelection)
                {
                    draws = draws + 1;
                }
                else if (userSelection == 1 && computerSelection == 3 || userSelection == 2 && computerSelection == 1 || userSelection == 3 && computerSelection == 2)
                {
                    userWins = userWins + 1;
                }
                else if (userSelection == 1 && computerSelection == 2 || userSelection == 2 && computerSelection == 3 || userSelection == 3 && computerSelection == 1)
                {
                    computerWins = computerWins + 1;
                }
                // Display results and statistics
                Console.WriteLine("\nYou have played {0} games with {1} wins, {2} draws, and {3} losses.", gamesPlayed, userWins, draws, computerWins);
                do
                {
                    Console.Write("Please make a selection: ");
                    // loop and test using TryParse()
                    while (!int.TryParse(Console.ReadLine(), out userSelection))
                    {
                        // invalid data type
                        Console.WriteLine("Invalid input.");
                        Console.Write("Please make a selection: ");
                    }
                    // test if input is within acceptable range
                    if (userSelection >= 1 && userSelection <= 4)
                    {
                        inputIsValid = true;
                    }
                    else
                    {
                        // valid integer, but out of acceptable range
                        Console.WriteLine("Number out of range.");
                    }
                } while (!inputIsValid);
            }
            if (gamesPlayed == 0 && userSelection == 4)
            {
                Console.WriteLine("\nGoodbye");
            }
            else if (gamesPlayed > 0 && userSelection == 4)
            {
                Console.WriteLine("\nGames played = " + gamesPlayed);
                Console.WriteLine("User wins = " + userWins);
                Console.WriteLine("Computer wins = " + computerWins);
                Console.WriteLine("Draws = " + draws);
            }
        Console.ReadLine();
    }
}
}

Answer 1

如果您发现自己多次编写几乎相同的内容，则应该寻找重构它的方法。下面是一个不必要的重复代码的示例：

if (userSelection == 1)
{
    Console.WriteLine("\nYou have selected Rock");
    gamesPlayed = gamesPlayed + 1;
}
else if (userSelection == 2)
{
    Console.WriteLine("\nYou have selected Paper");
    gamesPlayed = gamesPlayed + 1;
}
else if (userSelection == 3)
{
    Console.WriteLine("\nYou have selected Scissors");
    gamesPlayed = gamesPlayed + 1;
}

可以简化为：

Console.WriteLine("\nYou have selected " + tools[userSelection - 1]);
gamesPlayed++;

其中工具定义为：

string[] tools = { "Rock", "Paper", "Scissors" };