java - 循环中的数据验证输入

Question

我尝试了各种技术来检查此方法中用户输入的值。用户应该只能输入“1”或“0”。如果使用任何其他输入，则应出现错误消息并退出程序。有任何想法吗？我让它为第一个数字工作，但不是第二个到第十个数字。

    System.out.println("Enter a ten digit binary number.  Press 'Enter' after each digit.  Only use one or zero. :");

        binary[0] = keyboard.nextInt();

        for (index = 1; index < 10; index++)
            binary[index] = keyboard.nextInt();// fill array with 10 binary
                                                // digits from user. User
                                                // must press 'Enter' after
                                                // each digit.

Answer 1

尝试这个:

    Scanner scanner = new Scanner(System.in);
    if (scanner.hasNext())
    {
        final String input = scanner.next();
        try
        {
            int num = Integer.parseInt(input, 2);
        }
        catch (NumberFormatException error)
        {
            System.out.println(input + " is not a binary number.");
            //OR You may exit here, if you don't want to continue
        }
    }