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如何使用scanner（5个答案）处理由无效输入（inputmismatchexception）引起的无限循环
11天前关门了。
我是一个相当新的编程，我有麻烦，我的程序不断循环，当我试图处理一个问题 InputMisMatch 例外。
我有一个接受用户输入的菜单，然后使用switch语句来处理输入。我试图让我的程序处理两个异常。首先是确保输入实际上是一个整数，其次是确保整数在菜单的范围内。我在try块中使用了nextint（）方法。try块中有switch语句，它使用默认大小写来处理不在范围内的输入
但是，当用户输入整数以外的输入时，catch块会不断循环。似乎我没有在某个地方更新循环中的用户输入，但是我不知道在哪里更新它。
现在，我不关心switch案例中的内容（尽管我也想在它们内部实现相同的循环特性），它只是外部循环的逻辑。
这是我的密码：
任何指导都将不胜感激。谢谢！

public class Main {

    // set up scanner for user input
    public static Scanner keyboard = new Scanner(System.in);

    public static void main(String[] args) {
        // welcome message
        welcome();

        //declare user choice variables
        int menuSelection;
        int discSelection;

        boolean isInputValid = true ;

        do { // keep looping until user input is valid
            try {
                /*
                    We can expect an error from user input
                    1. Input is not an integer
                    2. Input is not in range
                 */

                isInputValid = true;
                displayMainMenu();
                menuSelection = keyboard.nextInt();
                System.out.println(); //print new line

                //Menu Logic
                switch (menuSelection) {
                    case 0: { // Exit Application
                        break;
                    }
                    case 1: { // Search
                        searchDiscMenu(); //Display the search menu
                        discSelection = keyboard.nextInt(); // get user choice
                        if (discSelection == 1) {
                            System.out.println("Disc.Music.searchMusic()");
                        } else if (discSelection == 2) {
                            System.out.println("Disc.Game.searchGame()");
                        }
                        break;
                    }
                    case 2: { // Add
                        addDiscMenu(); //Display add menu
                        discSelection = keyboard.nextInt(); // get user choice
                        if (discSelection == 1) {
                            System.out.println("Disc.Music.addMusic()");
                        } else if (discSelection == 2) {
                            System.out.println("Disc.Game.addGame();");
                        }
                        break;
                    }
                    case 3: { // Remove
                        removeDiscMenu(); //Display remove menu
                        discSelection = keyboard.nextInt(); // get user choice
                        if (discSelection == 1) {
                            System.out.println("Disc.Music.removeMusic();");
                        } else if (discSelection == 2) {
                            System.out.println("Disc.Game.removeGame();");
                        }
                        break;
                    }
                    case 4: { // View
                        viewDiscMenu(); //Display view menu
                        discSelection = keyboard.nextInt(); // get user choice
                        if (discSelection == 1) {
                            System.out.println("Disc.Music.viewMusic();");
                        } else if (discSelection == 2) {
                            System.out.println("Disc.Music.viewMusic();");
                        }
                        break;
                    }
                    case 5: { // Sort
                        sortDiscMenu(); //Display sort menu
                        discSelection = keyboard.nextInt(); // get user choice
                        if (discSelection == 1) {
                            System.out.println("Disc.Music.viewMusic();");
                        } else if (discSelection == 2) {
                            System.out.println("Disc.Music.viewMusic();");
                        }
                        break;
                    }
                    case 6: { // Write
                        writeDiscMenu(); //Display write menu
                        discSelection = keyboard.nextInt(); // get user choice
                        if (discSelection == 1) {
                            System.out.println("Disc.Music.viewMusic();");
                        } else if (discSelection == 2) {
                            System.out.println("Disc.Game.writeGameFile();");
                        }
                        break;
                    }
                    case 7: { // Read
                        readDiscMenu(); //Display read menu
                        discSelection = keyboard.nextInt(); // get user choice
                        if (discSelection == 1) {
                            System.out.println("Disc.Music.readMusicFile();");
                        } else if (discSelection == 2) {
                            System.out.println("Disc.Game.readGameFile();");
                        }
                        break;
                    }
                    default: { // Handle exception
                        isInputValid = false;
                        System.out.println("Error: Selection Not In Range"); // If the input is an int but not in range
                        break;
                    }
                }
            } catch (InputMismatchException e) { // Handles user typing in a char, double etc. instead of int
                isInputValid = false;
                System.out.println("Error: Unrecognised Input");
            }
        } while (!isInputValid);

        // Exit application safely
        System.out.println("Finished"); // temporary message

    }