如何使用hasNextInt（）来捕获异常？我需要Int，但如果输入是字符，那就是坏的 [英] How can I use hasNextInt() to catch an exception? I need Int but if input is character, that is bad

问题描述

我一直在试图阻止例外，但我无法弄清楚如何。
我试过 parseInt ， java.util.NormalExceptionMismatch 等。

I have been trying to stop the exceptions but I cannot figure out how. I tried parseInt, java.util.NormalExceptionMismatch etc.

有谁有任何洞察力如何解决这个问题？格式化由于复制和粘贴而有点偏差。

Does anyone have any insight how to fix this problem? Formatting is a bit off due to copy and paste.

do
{
   System.out.print(
           "How many integers shall we compare? (Enter a positive integer):");
   select = intFind.nextInt();
   if (!intFind.hasNextInt()) 
       intFind.next();
       {
           // Display the following text in the event of an invalid input
           System.out.println("Invalid input!");
       }
}while(select < 0)

尝试：

 do
    {
       System.out.print(
                   "How many integers shall we compare? (Enter a positive integer):");
       select = intFind.nextInt();
       {
            try{
                   select = intFind.nextInt();
               }catch (java.util.InputMismatchException e)
            {
               // Display the following text in the event of an invalid input
               System.out.println("Invalid input!");
               return;
            }
       }
    }while(select < 0)

推荐答案

在我看来，你想跳过一切，直到你得到一个整数。这里的代码跳过除整数之外的任何输入。

It seems to me that you want to skip everything until you get an integer. This code here skips any input except an integer.

只要没有整数可用（while（！in.hasNextInt（）））丢弃可用的输入（in.next）。当整数可用时 - 读它（int num = in.nextInt（）;）

As long as there is no integer available (while (!in.hasNextInt())) discard the available input (in.next). When integer is available - read it (int num = in.nextInt();)

public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        while (!in.hasNextInt()) {
            in.next();
        }
        int num = in.nextInt();
        System.out.println("Thank you for choosing " + num + " today.");
    }
}

这篇关于如何使用hasNextInt（）来捕获异常？我需要Int，但如果输入是字符，那就是坏的的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！