Question

我试图理解为什么我的代码只能工作一次然后有时根本不工作。有时它会接受我输入的字符串，然后有时它根本不会工作。请指出我正确的方向。

static int yourChoice, computerChoice;
static String userChoice; 
static String play = " ";
static int tieGames;
static int wonGames;
static int lossGames;
static int totalGames;


public static void main (String args[]){
        //Variable declaration
         //your choice versus the computer choice will be evaluated
         //the input





         do{
             PrintExplanation();

            String userChoice;
            userChoice =JOptionPane.showInputDialog(null, "Enter one of the following as your choice: \n Rock: (valid choices include 0, r, rock) \n Paper: (valid choices include 1, p, paper) \n Scissors: (valid choices include 2, s, scissors)");
            yourChoice = Integer.parseInt(userChoice);

            ConvertStringtoNum(userChoice);

            yourChoice= ConvertStringtoNum(userChoice);


            while(yourChoice < 0 || yourChoice > 2){
                JOptionPane.showMessageDialog(null,"Please only type in 0, 1, 2, r, p, s, rock, paper, or sissors for your choice!");

                if(yourChoice == 0){
                     break;
                 }
                 else if(yourChoice == 1){
                     break;
                 }
                 else if(yourChoice == 2){
                     break;
                 }

                userChoice =JOptionPane.showInputDialog(null, "Enter one of the following as your choice: \n Rock: (valid choices include 0, r, rock) \n Paper: (valid choices include 1, p, paper) \n Sissors: (valid choices include 2, s, sissors)");



            }


            computerChoice = GetComputerChoice();
            DetermineWinner(yourChoice,computerChoice);
            totalGames++;

            play = JOptionPane.showInputDialog("Do you want to play again? yes or no?!");

            if(play.equalsIgnoreCase("no")) {
                break;
                }

        }while(play.equalsIgnoreCase("yes"));

         JOptionPane.showMessageDialog(null,"Total Games: "+totalGames+ "\n Total Wins: "+wonGames+ "\n Total Losses: " +lossGames+ "\nTotal Tied Games: " +tieGames);

}

public static void PrintExplanation(){
            //Welcome screen and show the basic rule to user
    JOptionPane.showMessageDialog(null,"Welcome to the Rock, Paper, Sissors Game! \n Here are the rules:\nScissor cuts paper, paper covers rock, and rock breaks scissors. \n 0:Rock\n1: Paper\n2:Scissors");

}

public static String GetUserChoice(String userChoice){
    //Acquire a users choice
    userChoice =JOptionPane.showInputDialog(null, "Enter one of the following as your choice: \n Rock: (valid choices include 0, r, rock) \n Paper: (valid choices include 1, p, paper) \n Scissors: (valid choices include 2, s, scissors)");
    yourChoice = Integer.parseInt(userChoice);
    return userChoice ;

}

public static int ConvertStringtoNum(String userChoice){


    if (userChoice.equals("rock") || userChoice.equals("0")){
        yourChoice = 0;
    }
    else if(userChoice.equals("r") || userChoice.equals("0")){
    yourChoice = 0;
    }

    else if(userChoice.equals("paper") || userChoice.equals("1")){
        yourChoice = 1;
        }
    else if(userChoice.equals("p") || userChoice.equals("1")){
        yourChoice = 1;
        }
    else if(userChoice.equals("scissors") || userChoice.equals("2")){
        yourChoice = 2;
        }
    else if(userChoice.equals("s") || userChoice.equals("2")){
        yourChoice = 0;
        }

    return yourChoice = 1;
}






    public static int GetComputerChoice(){
        computerChoice = (int)(Math.random() * 3);

        return computerChoice = (int)(Math.random() * 3);
    }

public static int DetermineWinner(int yourChoice, int computerChoice){
        //determines the winner
        if(yourChoice == computerChoice){
            JOptionPane.showMessageDialog(null,"It's a tie!");
            tieGames++;
        }
    else if (yourChoice==0 && computerChoice==2 || userChoice.equals("r") && computerChoice==2 || userChoice.equals("rock") && computerChoice==2){

        JOptionPane.showMessageDialog(null,"You chose:Rock \n Computer chose:Scissors \n Rock beats Scissors You WIN!");
            wonGames++;
        }
        else if (yourChoice==1 && computerChoice==0 || userChoice.equals("p") && computerChoice==0 || userChoice.equals("paper") && computerChoice==0){


                        JOptionPane.showMessageDialog(null,"You chose:Paper \n Computer chose:Rock \n Paper beats Rock You WIN!");
                        wonGames++;

    }
    else if (yourChoice==2 && computerChoice==1 || userChoice=="s" && computerChoice==1 || userChoice=="sissors" && computerChoice==1){

                        JOptionPane.showMessageDialog(null,"You chose:Sissors \n Computer chose:Rock \n Scissors beats Paper You WIN!");
                        wonGames++;
    }
    else if(yourChoice==1 && computerChoice==2 || userChoice=="p" && computerChoice==2 || userChoice=="paper" && computerChoice==2){

                        JOptionPane.showMessageDialog(null,"You chose:Paper \n Computer chose:Scissors \n Paper loses against Scissors YOU LOSE! :-(");
                        lossGames++;
                    }
    else if(yourChoice==2 && computerChoice==0 || userChoice=="s" && computerChoice==0 || userChoice=="sissors" && computerChoice==0){

        JOptionPane.showMessageDialog(null,"You chose:Scissors \n Computer chose:rock \n Scissors lose against Rock YOU LOSE! :-(");
            lossGames++;
                    }

else if (yourChoice==0 && computerChoice==1 || userChoice=="r" && computerChoice==1 || userChoice=="rock" && computerChoice==1){

        JOptionPane.showMessageDialog(null,"You chose:Rock  \n Computer chose:Paper \n Rock loses against Paper YOU LOSE! :-(");
        lossGames++;
    }
        return computerChoice;
}

}

Answer 1

@juned是对的

这对于整数来说是可以的

yourChoice==0 && computerChoice==2

这是比较字符串的方法： userChoice.equals("r")

将所有字符串比较转换为equals()

你发了很多代码，但这是一个例子：

else if (yourChoice==2 && computerChoice==1 || userChoice=="s" && computerChoice==1 || userChoice=="sissors" && computerChoice==1){

Answer 2

所以从你到目前为止发布的代码中我可以看到三个问题：

userChoice =JOptionPane.showInputDialog(null, "Enter one of the following as your choice: \n Rock: (valid choices include 0, r, rock) \n Paper: (valid choices include 1, p, paper) \n Scissors: (valid choices include 2, s, scissors)");
yourChoice = Integer.parseInt(userChoice);

ConvertStringtoNum(userChoice);

yourChoice= ConvertStringtoNum(userChoice);

您尝试解析userChoice，但仍然不知道它是否是Integer。如果玩家输入的内容不是0, 1或2，则会引发NumberFormatException。

因为您已经拥有方法ConvertStringtoNum，并且您将yourChoice覆盖到其结果，无论如何您可以完全发出行yourChoice= ConvertStringtoNum(userChoice);而不会冒险抛出NumberFormatException

此外，您无需再拨打ConvertStringtoNum两次。

更好：

userChoice =JOptionPane.showInputDialog(null, "Enter one of the following as your choice: \n Rock: (valid choices include 0, r, rock) \n Paper: (valid choices include 1, p, paper) \n Scissors: (valid choices include 2, s, scissors)");

yourChoice= ConvertStringtoNum(userChoice);

然后第二个问题是方法ConvertStringtoNum本身。

你写了很多if {} else if {}来获得正确的yourChoice值，但最后你写了return yourChoice = 1所以无论用户的输入是什么，你都会返回{{1}在这个方法中。您只需将最后一行更改为1，一切都应该有效。

第三个问题是方法return yourChoice;。

您使用DetermineWinner。要比较字符串，你应该使用userChoice=="sissors"（就像你大部分时间一样。其次，此时你甚至不需要再看.equals，因为你已经将它的值解析为{{ 1}}。因此，您也可以简单地从userChoice中删除与yourChoice的每次比较。

userChoice和DetermineWinner的更简洁方式：

DetermineWinner

需要帮助了解为什么程序无法正常运行

2 个答案: