Question

所以这是我的主要课程。

import java.util.Scanner;
import java.util.Random;
public class seu03
{
public static void main (String[] args)
{
int option = 0;
option = seu03Methods.seu03Menu();
    while(option != 9)
        {
switch (option)
    {
    case 1:
        seu02.calculator();
        break;
    case 2:
        seu03Methods.sentenceAnalysis();
        break;
    case 3:
        seu03Methods.rollDice();
        break;
    case 4:
        seu03Methods.bigMoney();
        break;
    case 9:
        System.out.println("Exiting seu03...");
        System.exit(0);
        break;
    default:
        System.out.println("Invalid selection.");
        break;
    }
            }
} //end of main
} //end of class

这就是“方法”类。

    import java.util.Scanner;
    import java.util.Random;
    public class seu03Methods
{
    public static int seu03Menu()
    {
    int option = 0;
    Scanner console = new Scanner(System.in);   
    System.out.println("-------------------------------------");
    System.out.println("|         Welcome to seu03!         |");
    System.out.println("|-----------------------------------|");
    System.out.println("| Choose an option below:           |");
    System.out.println("|                                   |");
    System.out.println("| 1.  Calculator                    |");
    System.out.println("| 2.  Sentence Analysis             |");
    System.out.println("| 3.  Roll a 6-sided die            |");
    System.out.println("| 4.  Play Big Money!               |");
    //System.out.println("| 5. randomRange            |");
    //System.out.println("| 6. stubMethod            |");
    System.out.println("| 9.  Exit                          |");
    System.out.println("-------------------------------------");
    option = console.nextInt();
    return option;
    }
    public static void sentenceAnalysis()
    {
    Scanner console = new Scanner(System.in);
    String userString = new String("");
    System.out.println("-------------------------------------");
    System.out.println("Please enter a sentence for analysis:");
    userString = console.nextLine();
    System.out.println("The sentence to analyze is: " + userString);
    System.out.println("The sentence is " + userString.length() + " characters long.");
    System.out.println("The first character of the sentence is " + userString.charAt(0));
    System.out.println("The middle charchter of the sentence is " + userString.charAt(userString.length()/2));
    System.out.println("The last character of the sentence is " + userString.charAt(userString.length()-1));
    System.out.println("Thanks for using our 1323 System!");
    System.out.println("-------------------------------------");
    return;
    } //end of sentenceAnalysis
    public static void rollDice()
    {
    Random gener = new Random();
    int die = 0;
    System.out.println("-------------------------------------");
    System.out.println("Welcome to Roll Dice!");
    System.out.println("The program will now roll a single six-sided die.");
    die = gener.nextInt(6) + 1;
    System.out.println("Result: " + die);
    System.out.println("Thanks for using our 1323 System!");
    System.out.println("-------------------------------------");
    return;
    } //end of rollDice
    public static void bigMoney()
    {
    Scanner console = new Scanner(System.in);
    Random gener = new Random();
    int rnum = 0;
    int guess1 = 0;
    int guess2 = 0;
    int guess3 = 0;
    System.out.println("-------------------------------------");
    System.out.println("Welcome to Big Money!");
    rnum = gener.nextInt(10) + 1;
    System.out.println("A whole number between 1 and 10 inclusive has been generated. You will have three chances to guess the number.");
    System.out.println("Here is the random number for testing purposes: " + rnum);
    System.out.println("What is your first guess?");
    guess1 = console.nextInt();
    if(guess1 == rnum)
        {
        System.out.println(" Big Money! You win $100!");
        }
    else
        {
        System.out.println("No good! What is your second guess?");
        guess2 = console.nextInt();
            if(guess2 == rnum)
            {
            System.out.println("Medium Money! You win $50!");
            }
            else
                {
                System.out.println("No good! What is your third guess?");
                guess3 = console.nextInt();
                    if(guess3 == rnum)
                    {
                    System.out.println("Little Money! You win $1!");
                    }
                        else
                        {
                        System.out.println("Sorry! You didn't win any money this time. Better luck next time!");
                        }
                }
            }   
    System.out.println("Thanks for playing Big Money!");
    System.out.println("Thanks for using our 1323 System!");
    System.out.println("-------------------------------------");
    return;
    } //end of bigMoney
} //end of class

如果我选择一个选项，比如3，该选项将永远重复（直到我关闭命令行）。我星期二错过了课程（感谢你没有发出警报！）因此错过了关于循环的讲座。：/如果有人可以提供一些帮助（可能是一些指示？），将不胜感激！我想要的是选择一个选项，按照该方法执行操作，然后返回菜单选择另一种方法，直到用户选择“9”并退出。而且如果以后我也需要摆脱那种可怕的嵌套。

Answer 1

将option = seu03Methods.seu03Menu();移动到while循环中（向下移动两行到while(option != 9){..。）您永远不会在循环中更改option，因此它始终为3

Answer 2

while(option != 9)
        {
switch (option)
    {
    case 1:
        seu02.calculator();
        break;
    case 2:
        seu03Methods.sentenceAnalysis();
        break;
    case 3:
        seu03Methods.rollDice();
        break;
    case 4:
        seu03Methods.bigMoney();
        break;
    case 9:
        System.out.println("Exiting seu03...");
        System.exit(0);
        break;
    default:
        System.out.println("Invalid selection.");
        break;
    }
            }

你永远无法得到你的情况：9，退出....因为while循环告诉它跳过开关，如果int是9（我假设会关闭应用程序）尝试更改此

while(option != 9)

Java菜单循环无限重复

2 个答案: