Question

我在程序中创建是/否输入时遇到问题。我希望用户能够在最后一个print语句之后输入y / n，但我不确定如何实现它。我知道它很可能包括布尔值或if / else语句，但我不太确定。有什么帮助吗？

import java.util.*;
import java.io.*; 
import java.util.Scanner;

public class Person 
{
public static void main(String[]args) 
{

    int age;
    String name;

    Scanner scan = new Scanner(System.in);

    System.out.println("Enter in your age.");
    age = scan.nextInt();

        if (age >= 10 && age < 18) 
        {
            System.out.println("So you're a kid, huh?");
        } 

        else if (age < 10)
        {
            System.out.println("Nice try.");
            System.exit(0);
        }
        else if (age >= 18 && age <= 100)
        {
            System.out.println("So you're an adult, huh?");
        }
        else if (age > 100)
        {
            System.out.println("Nice try.");
            System.exit(0);
        }

        Scanner in = new Scanner(System.in);
        System.out.println("Enter in your name");
        name = in.nextLine();

        System.out.println("So you're " + age + " years old and your name is " + name + "?");

        System.out.println("y/n");
        }
}

Answer 1

String answer;
boolean yn;

System.out.println("y/n");
while (true) {
  answer = in.nextLine().trim().toLowerCase();
  if (answer.equals("y")) {
    yn = true;
    break;
  } else if (answer.equals("n")) {
    yn = false;
    break;
  } else {
     System.out.println("Sorry, I didn't catch that. Please answer y/n");
  }
}

Answer 2

这是你需要的吗？

String answer = in.nextLine()
Boolean yn = (answer.equalsIgnoreCase("Y") ? true : false);

或者，您可以使用更短的形式：

Boolean yn = (answer.equalsIgnoreCase("Y"));

如果您有其他意思，请发表澄清。

Answer 3

只需添加boolean answer = in.nextLine().toLowerCase().startsWith("y");

因此，如果您输入以answer开头的任何内容，基本上它会将y设置为true。否则就是假的。

Answer 4

您将读入一个字符串并将其与文字“y”进行比较。比较产生一个布尔值。

你可以扩展这个以首先检查它是“y”还是“n”并且如果它既不是也不是要接受其他等价物如“是”和“否”则会抱怨。

在任何情况下，您的布尔值都是通过与文字进行比较来实现的。

Answer 5

试试这个，

boolean answer = "y".equalsIgnoreCase(in.nextLine());

Answer 6

您可以使用do while loop，例如：

import java.util.Scanner;

public class Test {
    public static void main(String[] args) {

        int age;
        String name;
        String input = "y";
        do {
            Scanner scan = new Scanner(System.in);

            System.out.println("Enter in your age.");
            age = scan.nextInt();

            if (age >= 10 && age < 18) {
                System.out.println("So you're a kid, huh?");
            }

            else if (age < 10) {
                System.out.println("Nice try.");
                System.exit(0);
            } else if (age >= 18 && age <= 100) {
                System.out.println("So you're an adult, huh?");
            } else if (age > 100) {
                System.out.println("Nice try.");
                System.exit(0);
            }

            Scanner in = new Scanner(System.in);
            System.out.println("Enter in your name");
            name = in.nextLine();

            System.out.println("So you're " + age
                    + " years old and your name is " + name + "?");

            Scanner sc = new Scanner(System.in);
            System.out.println("y/n");
            input = sc.nextLine();
        } while (input.equalsIgnoreCase("y"));
    }
}

Answer 7

我弄清楚了。

import java.util.Scanner;

public class MuseumHours2 {
    public static void main(String[] args) {
        String day;
        boolean yn = true;
        boolean userContinue;
        String answer;

        Scanner stdIn = new Scanner(System.in);


        do {
            System.out.println("Hello, thank you for visiting the Museum 
    website. For what day would you like to check our hours of operation?");
            day = stdIn.nextLine();

            System.out.println("Is today a holiday? Enter y or n.");
            answer = stdIn.nextLine();
                if (answer.equals("y")) {
                    yn = true;
                } else if (answer.equals("n")) {
                    yn = false;
                } else { 
                    System.out.println("Sorry, I didn't understand. Please reply y or n.");
                }

            switch (day) {
            case "Monday":
                System.out.println("Closed.");
                break;

            case "Tuesday":
                if (yn) {
                    System.out.println("We are open from 1:00 to 4:00.");
                } else {
                    System.out.println("We are open from 12:00 to 5:00.");
                }
                break;
            case "Wednesday":
                if (yn) {
                    System.out.println("We are open from 2:00 to 5:00.");
                } else { 
                    System.out.println("We are open from 1:00 to 6:00.");
                    break;
                }
            case "Thursday":
                System.out.println("Closed.");
                break;
                }
            System.out.println("Do you want to re-run the program? Type y or n.");
        } while (userContinue = "y".equalsIgnoreCase(stdIn.nextLine()));
    }
}

Answer 8

这里是一个示例

 public static void main(String[] args) {

        Scanner sc = new Scanner(System.in);
        boolean yn;
        String ageq;

        System.out.println("Please enter your age: ");
        ageq = sc.next();

        System.out.println("You entered " + ageq + " is this correct?");
        System.out.println("y/n");
        OUTER:
        while (true) {
            ageq = sc.next().trim().toLowerCase();
            switch (ageq) {
                case "y":
                    yn = true;
                    break OUTER;
                case "n":
                    yn = false;
                    break OUTER;
                default:
                    System.out.println("Sorry, I didn't get that. Please enter y/n");
                    break;
            }
        }

  }

Answer 9

使用import json from requests import Session from bs4 import BeautifulSoup URL = 'https://fr.trustpilot.com/review/jardiland.com?page=2' session = Session() r = session.get(URL) soup = BeautifulSoup(r.text) data = soup.find('script',{'type':'application/ld+json'}) data_json = json.loads(data.getText(strip=True)) # now you can assess data as dictionary，对于“是”和“是”，它将返回true

是/否使用布尔值或if / else？

9 个答案: