Question

我正在制作一个简单的for循环，以遍历ArrayList并向其中添加对象，但是当我输入第一个对象时，什么也没发生。程序似乎没有继续循环。这是我所拥有的：

for (int i = 0; i < (numPlayers.nextInt()-1); i++){
    System.out.println("what is player " + (i + 1) + " name?");
    Scanner namePlayer = new Scanner(System.in);
    String playerName = namePlayer.nextLine();
    playerList.add(new Player(playerName));
}

玩家对象的构造函数也非常简单

public Player(String name) {
    this.name = name
}

Answer 1

如果可能，您只需定义一次循环限制：

int numberOfPlayers = numPlayers.nextInt()-1;
for (int i = 0; i < numberOfPlayers; i++){
    System.out.println("what is player " + (i + 1) + " name?");
    Scanner namePlayer = new Scanner(System.in);
    String playerName = namePlayer.nextLine();
    playerList.add(new Player(playerName));
}

您需要确保您要循环迭代多次。

Answer 2

public static void main(String[] args)
    {
        Scanner numPlayers = new Scanner(System.in);
        ArrayList<Player> playerList = new ArrayList<>();
        int input = numPlayers.nextInt();

        for (int i = 0; i < input; i++){
            System.out.println("what is player " + (i + 1) + " name?");
            String playerName = numPlayers.next();
            playerList.add(new Player(playerName));
        }

    }

您应该在for循环之外声明scanner对象。代码的问题是，每次输入字符串后，都需要为(int i = 0; i < (numPlayers.nextInt()-1); i++)提供一个整数，这就是为什么如果您提供除整数以外的任何内容都会给InputMismatchException的原因。因此，您必须在for循环外初始化输入常量，否则执行会动态变化。

Java没有继续循环

2 个答案: