如何使用 JOptionPane 设置数组的长度

Question

我需要创建一个数组。长度必须使用JOptionPane进行设置。此外，我还必须用随机数填充数组。这就是我走了多远。

import javax.swing.*;
import java.util.Arrays;
import java.util.Random;
public class Aufgabe2
{
public String a;
public static void main(String[] args)
{
String a = JOptionPane.showInputDialog("How big should the array be?");
try
{
Integer.parseInt(a);
int meinArray[];
meinArray = new int[a];
Random rand = new Random();
for (int i = 0; i < a; i++)
{
meinArray[i] = rand.nextInt();
}
System.out.println(Arrays.toString(meinArray));
}
catch (NumberFormatException e)
{
System.out.println(a + " isn`t a valide input. Please insert a number");
}
}
}

Answer 1

您需要将Integer.parseInt(a)的结果存储到某个变量中，然后使用它，例如

int x= Integer.parseInt(a);
int meinArray[];
meinArray = new int[x];
Random rand = new Random();
for (int i = 0; i < x; i++){
meinArray[i] = rand.nextInt();
}

Answer 2

您缺少解析的整数赋值

int size=Integer.parseInt(a);//you are missing int size= here
int[] meinArray = new int[size];
Random rand = new Random();
for (int i = 0; i < s; i++)
{
meinArray[i] = rand.nextInt();
}
System.out.println(Arrays.toString(meinArray));