向数组菜单驱动中添加数字

Question

我有一个问题。我刚刚开始学习Java中的数组。我了解数组以及它们的工作原理，几乎存储了多少数据。但这是我的问题，我正在尝试使用菜单将现有整数添加到数组中。但是，我不明白为什么我的程序似乎不起作用。

import java.util.Scanner;
public class ArraySorting
{
public static void main(String[] args)
  {
     int option;
     int integer = 0;
     int optionOne;


     Scanner kb = new Scanner(System.in);
     System.out.println("Please enter a non-negative integer: ");
     integer = kb.nextInt();

     while((integer < 0))
     {
        System.out.println("I am sorry that is not a non-negative integer.");
        System.out.println("");
        System.out.println("Please enter a non-negative integer: ");
        integer = kb.nextInt();
     }
     option = displayMenu(kb);
     while (option != 6)
     {
        switch (option)
        {
           case 1:
              optionOne();
              System.out.println("Done with Option 1. Please enter another option.");
              break;
           case 2:
              //optionTwo();
              System.out.println("Done with Option 2. Please enter another option.");
              break;
           case 3:
              //optionThree();
              System.out.println("Done with Option 3. Please enter another option.");
              break;
           case 4:
              //optionFour();
              System.out.println("Done with Option 4. Please enter another option.");
              break;
           case 5:
              //optionFive();
              System.out.println("Done with Option 5. Please enter another option.");
              break;
        }
            option = displayMenu(kb);
     }
     if (option == 6)
     {
        System.out.println();
        System.out.println("Thank you. Have a nice day.");
     }
}
  private static int displayMenu(Scanner kb)
  {
     int option = 0;
     while (option != 1 && option != 2 && option != 3 && option != 4 && option !=5 && option !=6)
     {
        System.out.println("tt1. Add a number to the arrayntt2. Display the meanntt3. Display the median ntt4. Print the array to the screen ntt5. Print the array in reverse order ntt6. Quit");
        option = kb.nextInt();
        if (!(option == 1 || option == 2 || option == 3 || option == 4 || option == 5 || option == 6))
           System.out.println("I am sorry that is an invalid choice. Please try again.");
     }
     return option;
  }

  private static int optionOne()
  {
     Scanner input = new Scanner(System.in);
     int[] numbers = new int[99];
     for (int i = 0; i < numbers.length; i++)
           {
              System.out.println("Please enter number");
              numbers[i] = input.nextInt();
           }
    return numbers;       
 }

}

Answer 1

代码有问题。

问题是你的函数选项一个应该返回一个整数数组。您已将返回类型设置为单个整数。

其中之一需要改变

如果必须返回数组，我认为是这种情况，那么函数应该看起来像这样。

 private static int[] optionOne()
  {
     Scanner input = new Scanner(System.in);
     int[] numbers = new int[99];
     for (int i = 0; i < numbers.length; i++)
           {
              System.out.println("Please enter number");
              numbers[i] = input.nextInt();
           }
    return numbers;       
 }

干杯。