程序结束时出现循环问题，无法退出

Question

好的，谢谢，我已经找到退出循环了。

现在我的问题是我正在尝试测试 int newScore 以确保其值在 1 到 100 之间。循环中途工作。如果我在参数之外输入一个值，它会循环并再次询问。但是，当我在参数中输入一个值时，它不会中断循环并继续程序的下一部分（询问下一个测试分数，或者如果没有更多分数则计算平均值）这是我更新的代码试试这个循环：

        do {
          while (scoreValid) {
            while (tv) {
              try {
                System.out.println("Please enter test score # " + counter);
                newScore = Integer.parseInt(scan.nextLine());
                if (newScore >= 1 && newScore <= 100) {
                  scoreValid = true;
                  tv = false;
                  counter++;
                  totalScore = totalScore + newScore;
                  break;
                } else {

                  System.out.println("Sorry, you must enter a number between 1 and 100.");
                  tv = true;
                  continue;
                }

              } catch (Exception e) {
                System.out.println("Sorry, I didn't catch that");
                continue;
              }
            }
          }
        } while (counter <= numberTests);

这里是原代码....

/**
 * This app will average test scores and tell you what letter grade you received.
 *
 * @jordan.hawkes
 * @1.0
 */

import java.util.Scanner;
public class TestScoreCalculator {
  public static void main(String[] args) {

      String first; // First Name entered by user
      String last; // Last Name entered by user
      String newTestAnswer; // answer for entering another test score
      String redoAnswer; // answer to rerun program
      int avg; // Average test score
      int totalScore = 0; // Total Running Test Score
      int newScore; // Test Score Entered by User
      int counter = 1; // Number of Scores Entered
      int testNumber; // Test # counter
      int numberTests = 0; // Number of Tests entered by user
      boolean scoreValid = false; // boolean to validate score       
      boolean newTest = false; // boolean to validate entering another test
      boolean redo = false; // boolean to rerun program
      boolean numberTestsValid = false; // boolean to validate number of tests
      boolean test = false; // test boolean to validate exit/rerun

      Scanner scan = new Scanner(System.in);

      System.out.print("Please enter your first name: ");
      first = scan.nextLine();

      System.out.print("Hello, " + first + ", please enter your last name: ");
      last = scan.nextLine();

      while (redo = true) {
        while (numberTestsValid = true) {
          try {
            System.out.println("Thanks, " + first + ", how many test scores would you like to enter? ");
            numberTests = Integer.parseInt(scan.nextLine());
            numberTestsValid = true;
            break;
          } catch (Exception e) {
            System.out.println("Sorry, I didn't catch that");
            continue;
          }
        }

        do {
          while (scoreValid = true) {
            try {
              System.out.println("Great, please enter test score # " + counter);
              newScore = Integer.parseInt(scan.nextLine());
              scoreValid = true;
              counter++;
              totalScore = totalScore + newScore;
              break;
            } catch (Exception e) {
              System.out.println("Sorry, I didn't catch that");
              continue;
            }
          }
        } while (counter <= numberTests);

        testNumber = counter - 1;
        avg = (totalScore / testNumber);

        switch (avg / 10) {
          case 10:
            System.out.println("Congratulations " + first.charAt(0) + ". " + last + ", you got an A+!");
            break;
          case 9:
            System.out.println("Congratulations " + first.charAt(0) + ". " + last + ", you got an A!");
            break;
          case 8:
            System.out.println("Congratulations " + first.charAt(0) + ". " + last + ", you got a B!");
            break;
          case 7:
            System.out.println("Congratulations " + first.charAt(0) + ". " + last + ", you got a C!");
            break;
          case 6:
            System.out.println("Congratulations " + first.charAt(0) + ". " + last + ", you got a D!");
            break;
          default:
            System.out.println("Congratulations " + first.charAt(0) + ". " + last + ", you got an F!");

        }

        while (test = true) {
          System.out.println("type r to restart or q to quit");
          redoAnswer = scan.nextLine().trim().toLowerCase();
          if (redoAnswer.equals("r")) {
            test = false;
            totalScore = 0;
            counter = 1;
            redo = true;
            break;
          } else if (redoAnswer.equals("q")) {
            test = false;
            redo = false;
            System.out.println("Goodbye!");
            continue;
          } else {
            System.out.println("Sorry, I didn't catch that. Please type r to restart or q to quit");
            continue;
          }
        }
      }
    } //end main
} //end class

Answer 1

经典错误：

while (redo = true)

将true分配给redo并且总是true，它不会测试它。

将其更改为

while (redo == true)

或更好：

while (redo)

其他循环条件也是如此。

程序结束时出现循环问题，无法退出

loop issue at end of program, can't exit

loops

boolean

infinite

while-loop