Question

我有一个切换菜单，我希望它循环整个菜单，包括方向，但它只是循环我选择的操作。我该如何改变它？我从do / while切换到while循环。

 int count = 0;

    String first;
    String last;
    String num;
    Contact person;

    System.out.println("What would you like to do?");
    System.out.println("Type c to create");
    System.out.println("Tpe e to edit");
    System.out.println("Tpe d to delete");
    System.out.println("Type q to quit");

    Scanner input = new Scanner(System.in);
    char choice = input.next().charAt(0);

    AddressBook addressBook = new AddressBook();
    while ('q' != choice) {
        switch (choice) {

            case 'c':
                System.out.println("Enter first name, last name and phone number");

                addressBook.addContact();

                count++;

                System.out.println("Total number of contact: " + count);

                break;

            case 'e':
                System.out.println("Enter name to be edited");

                first = input.next();
                last = input.next();
                num = null;

                person = new Contact(first, last, num);
                addressBook.edit(person);

                break;
            case 'd':
                System.out.println("Enter name to be deleted");

                first = input.next();
                last = input.next();
                num = null;

                person = new Contact(first, last, num);

                addressBook.removeContact(person);
                break;
            default:
                System.out.println("Operation does not exist");
        }

    }
}

}

Answer 1

将char choice初始化为默认字符：

char choice = 'a';

然后移动所有这些：

System.out.println("What would you like to do?");
System.out.println("Type c to create");
System.out.println("Tpe e to edit");
System.out.println("Tpe d to delete");
System.out.println("Type q to quit");

choice = input.next().charAt(0);

在你的while循环中：

while ('q' != choice) {
    //show menu options
    //allow user to select a menu option

    //use switch to operate based on user decision

    //once the operation is complete, as long as the user didn't select q, 
    //the menu options show once more and allow another selection
}

Answer 2

无需使用choice。

1.将while ('q' != choice)更改为while (true)

2.在

中移动下面的代码

     System.out.println("What would you like to do?");
     System.out.println("Type c to create");
     System.out.println("Tpe e to edit");
     System.out.println("Tpe d to delete");
     System.out.println("Type q to quit");

3。添加一个额外的案例

 case 'q':

   break;

切换菜单Java

2 个答案: