java - 有没有办法在 createArray() 的子程序 print() 中打印 multArray？

Question

我想要两个子程序createArray()和print()。 Print() 将需要 createArray() 中的 multArray 变量，并且我已经编写了程序，以便数组不会在 main 中本地创建。我意识到我可以将 createArray 设置为 createArray(int a, int b) 但我决定不这样做。现在这会回来咬我吗？还是有办法让我在不进行建议的更改的情况下完成此任务？

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

public class Array {

    public static void main(String[] args) {

        Scanner scan = new Scanner(System.in);
        String newLine = System.lineSeparator();
        String choiceInput;
        boolean stop = false;
        boolean firstTime = true;


        while (stop == false){

            if (firstTime == true) {
                System.out.println("Welcome To The Multiplications Table Creator!" + newLine + newLine + "Would you like to:" + newLine + newLine + "Create          Print          Exit" + newLine + newLine + "Please enter one of the above in the space below: ");
            }
            else {
                System.out.println("Welcome Back!" + newLine + newLine + "Would you like to:" + newLine + newLine + "Create          Print          Exit" + newLine + newLine + "Please enter one of the above in the space below: ");
            }
            choiceInput = scan.nextLine().toUpperCase();

            if (choiceInput.equals("CREATE")) {
                createArray();
                firstTime = false;

                for (int count = 0; count < 10; count++) {
                    System.out.println(newLine);
                }

            }
            else if (choiceInput.equals("PRINT")) {
                print();
                firstTime = false;
            }
            else if (choiceInput.equals("EXIT")) {
                for (int count = 0; count < 10; count++) {
                    System.out.println(newLine);
                }
                System.out.print("Thank you for using the program!");
                for (int count = 0; count < 2; count++) {
                    System.out.println(newLine);
                }
                stop = true;
            }
            else System.out.println("You did not enter one of the above!");
        }
    }

    public static int[][] createArray() {

        Scanner s = new Scanner(System.in);
        String newLine = System.lineSeparator();
        int a;
        int b;

        System.out.print("How big would you like your multiplication table to be? (A x B)" + newLine + "A: ");
        a = s.nextInt();
        System.out.println(a + " x ");
        b = s.nextInt();

        int[][] multArray = new int[a][b];

        for (int countA = 1; countA <= a; countA++) { 
            for (int countB = 1; countB <= b; countB++) {
                multArray[countA - 1][countB - 1] = countA * countB;
            }

        }
        System.out.print("Creating .");
        delay(1000);
        System.out.print(" .");
        delay(1000);
        System.out.print(" .");
        delay(1000);
        System.out.println(newLine + "Done.");
        return multArray;

    }

    public static void print() {
        **//This is where I need to print multArray created above is it possible?**
    }

    public static void delay(int millis) {
        try {
            Thread.sleep(millis);
        } 
        catch (InterruptedException exp) {  
        }
    }
}

Answer 1

您的 createArray 方法返回一个 int[][] 数组，因此您可以执行类似的操作

int[][] multiArray = createArray();//将create array方法的结果存储在multiArray中

现在更改您的 print 方法以接受 int[][] 数组，如下所示

public static void print(int[][] multiArray); //接受 int[][] 数组作为参数的打印方法

当您调用类似这样的打印方法时，将 multiArray 传递给打印方法

print(multiArray) //将 createArray 的早期结果(multiArray)传递给 print 方法。

现在，在 print 方法中，您可以打印 multiArray。