java - 向现有的 java 程序添加循环？

Question

我需要修改我的程序，以便在需要时可以多次运行它。如果用户输入 Q 或 q，并且输入除请求的条目(或退出命令)以外的任何内容，我需要退出程序，问题将重复。 这是我到目前为止的代码:

import java.util.Scanner;

public class TemperatureLoop
{

    private static Scanner keyboard = new Scanner(System.in);

    public static void main(String[] args) 
    {

        System.out.println("Enter a temperature in degrees (for example 32.6): ");
        double temp;
        temp = keyboard.nextDouble();
        System.out.println("Enter 'F' (or 'f') for Fahrenheit or 'C' (or 'c') for Celsius: ");
        String letter = keyboard.next();
        double total = 0;
        //if Farenheit then do this equation
        if (letter.equals("F") || (letter.equals("f")))
        {
            total = ((temp-32)*5)/9; //convert the entered temperature to Celsius
            System.out.println(temp + " degrees F = " + total + " degrees Celsius");
        }
        else //if Celsius then do this
        if (letter.equals("C") || (letter.equals("c")) )
        {
            total = (((temp*9))/5)+32; //convert the entered temperature to Farenheit
            System.out.println(temp + " degrees C = " + total + " degrees Fahrenheit");
        }
    }
}

Answer 1

我建议将您所拥有的内容放入 while 循环中，如果用户输入“Q”或“q”，该循环就会中断。类似于下面的内容:

// Declare your breaking condition variable outside the while loop
boolean done = false;
while (!done){
   //  Your existing code here
   //  A conditional to check for 'Q' or 'q'
   //  set done to true if the above line evaluates as true.
}