Question

我想按Enter键退出循环。这该怎么做？现在，当我输入任何非数字值时，循环退出，然后按Enter键。如何通过输入任何内容退出并按Enter键？

ArrayList<Integer> numbers = new ArrayList<Integer>();
int numberIn;
Scanner scan = new Scanner(System.in);
System.out.println("Enter numbers!");

while (scan.hasNextInt()) {
    numberIn = scan.nextInt();
    numbers.add(numberIn);
}

System.out.println("Numbers: " + numbers + ".");

Answer 1

尝试hasNext()：

while (scan.hasNext("\\d+")) {
    numberIn = scan.nextInt();
    numbers.add(numberIn);
}

Answer 2

ArrayList<Integer> numbers = new ArrayList<Integer>();
int numberIn;
Scanner scan = new Scanner(System.in);
System.out.println("Enter numbers!");

String input;
while (!(input = scan.nextLine()).isEmpty()) {
    numberIn = Integer.parseInt(input);
    numbers.add(numberIn);
}

System.out.println("Numbers: " + numbers + ".");

Answer 3

这对我有用：

ArrayList<Integer> numbers = new ArrayList<Integer>();
int numberIn;
Scanner scan = new Scanner(System.in);
System.out.println("Enter numbers!");

String input;
while (!(input = scan.nextLine()).isEmpty()) {
    numberIn = Integer.parseInt(input);
    numbers.add(numberIn);
}

System.out.println("Numbers: " + numbers + ".");

如何退出此循环？

3 个答案: