1

有人可以帮我弄清楚为什么while语句不起作用吗？循环确实在 i = 3 之后停止，但如果 continueSurvey = 0 则不会停止。它会运行，但如果我将 continueSurvey 更改为 O，它不会退出循环。即使我进入进程并且我可以看到变量是0，循环继续。

import java.util.Scanner;

public class SurveyConductor 
{

    public static void main(String[] args) 
    {
        Survey a = new Survey(); 
        a.display();

        a.enterQuestions();   

        int continueSurvey = 1;
        int i = 0;

            while ((continueSurvey != 0) && (i < 3))
            {

                for (int row = a.getRespID(); row < 3; row++)
                {

                    System.out.println("Respondent " + (row+1) + " Please tell us how you would rate our: ");

                    for (int col = 0; col < 3; col++)
                    {
                        Scanner input = new Scanner(System.in);

                        System.out.println(a.presentQuestion(col) + ": ");
                        System.out.println("Enter your response (1-Strongly Disagree, 2-Disagree, 3-Neutral, 4-Agree, 5-Strongly Agree): ");
                        int response = input.nextInt();

                        if ((response < 1) || (response >5))
                        {
                            while ((response < 1) || (response > 5))
                            {
                                System.out.println("Your response must be between 1 and 5. Please try again.");

                                System.out.println(a.presentQuestion(col) + ": ");
                                System.out.println("Enter your response (1-Strongly Disagree, 2-Disagree, 3-Neutral, 4-Agree, 5-Strongly Agree): ");
                                response = input.nextInt();
                            } 
                        }

                        a.logResponse(row,col,response);
                        System.out.println();
                    }

                    a.displaySurveyResults();
                    System.out.println();
                    System.out.println("The top rated question is Question #" + a.topRatedQuestion() + ".");
                    System.out.println("The bottom rated question is Question #" + a.bottomRatedQuestion() + ".");
                    System.out.println();

                    Scanner input2 = new Scanner(System.in);
                    System.out.println("Are there any more repondents (0 - No, 1 - Yes): ");
                    continueSurvey = input2.nextInt(); 


                    a.generateRespondentID();
                    i++;
                }
            } 
    }
}
4

4 回答 4

2

You need to add a break inside your for loop. IE, 

if(continueSurvey == 0)
    break;

This will exit the for loop and allow the while loop to exit.

于 2013-08-06T16:56:01.503 回答
0

您在 while 循环中的条件是：

((continueSurvey != 0) && (i < 3))

这意味着当且仅当 continuSurvey != 0 且 i < 3 同时执行时，while 循环的内部块将被执行。您有具有不同条件的内部循环。我会使用调试器在内部循环中搜索问题。如果这个答案对您来说还不够，那么请指定您想要实现的目标。

于 2013-08-06T17:44:15.583 回答
0

您询问用户是否要继续的部分在此 for 循环中

for (int row = a.getRespID(); row < 3; row++)

不仅仅是你的while循环。这意味着它会一直询问直到 for 循环完成，只有当它最终回到 while 循环条件时才会退出。

于 2013-08-06T16:53:38.667 回答
-1

if you want to exit the loop if either continueSurvey is 0 OR i=3 you have to write the while loop like this:

while((continueSurvey != 0) || (i < 3)) {
    ...
}

the && (and) operator symbolises that both conditions have to be true in order for the loop to exit not one of them (|| or).

于 2013-08-06T16:55:45.910 回答