Question

我需要验证用户的输入，以便输入的值为double或int;然后将int / double值存储在数组中，并在用户输入无效数据时显示错误消息。

由于某些原因，如果用户输入无效数据，我的代码会崩溃您能否请查看下面的代码并告诉我可能出现的问题？

public static double[] inputmethod() {
    double list[] = new double[10];
    Scanner in = new Scanner(System.in);
    double number;
    System.out.println("please enter a double : ");

    while (!in.hasNextDouble()) {
        in.next();
        System.out.println("Wrong input, Please enter a double! ");
    }
    for (int i = 0; i < list.length; i++) {
        list[i] = in.nextDouble();
        System.out.println("you entered a double, Enter another double: ");

    }
    return list;
}

Answer 1

对于验证用户双重或不执行如下操作：

 public class TestInput {

    public static double[] inputmethod() {
        double list[] = new double[10];
        Scanner in = new Scanner(System.in);
        double number;
        System.out.println("please enter a double : ");

        for (int i = 0; i < list.length; i++) {
            while (!in.hasNextDouble()) {
                in.next();
                System.out.println("Wrong input, Please enter a double! ");
            }
            list[i] = in.nextDouble();
            System.out.println("you entered a double, Enter another double: ");

        }
        return list;
    }

    public static void main(String args[]) {
        inputmethod();
    }

}

Answer 2

你基本上已经走上了正轨！您所要做的就是将while loop用于验证用户输入for loop。你的代码看起来应该是这样的。

public class InputTest{

  public static double[] inputmethod() {
    double list[] = new double[10];
    Scanner in = new Scanner(System.in);
    double number;
    System.out.print("Please enter a double: ");

    for (int i = 0; i < list.length; i++) {
      while(!in.hasNextDouble()){
        in.next();
        System.out.print("Wrong input! Please enter a double: ");
      }
      System.out.print("You entered a double! Enter another double: ");
      list[i] = in.nextDouble();
    }
    return list;
  }

  public static void main(String args[]){
    double list[] = inputmethod();
  }
}

仅为int或double值验证用户的输入

2 个答案: