Question

我尝试编写一个程序，让您选择是否要注册或登录，如果选择作者明智，它会让您知道您只能选择注册或登录... 我有一个问题，程序有时卡在循环中，告诉我输入了错误的输入，虽然我键入“登录”，你不能摆脱这个循环。我得到的另一个问题是登录代码：我添加了等于用户count+1的user_id，我想检查登录中的用户和传递是否正确，并且for循环覆盖用户数量并检查用户是否输入等于user_id的每个用户的密码，我只是不知道怎么做我想也许给任何用户的对象计数，所以我可以在我的用户逐个检查用户for for user_id.username和user_id.password.

import java.util.Scanner;

public class users {
    public String user_name;
    public int user_id = 1;
    private String password;
    public static int count = 1;
    public static String input;

    public users(String Ruser, String Rpassword) {

        this.user_id = count++;
        this.user_name = Ruser;
        this.password = Rpassword;
        count++;

        System.out.printf("User %s has been crated \n", Ruser);
        System.out.printf("Enter 'login' to log in or 'register' to open another account");

    }

    public static void login(String Luser, String Lpassword) {
        for (int i = 1; i <= count; i++) {
            System.out.printf("Enter 'login' to log in or 'register' to open another account");
            // user_id.users
            // if(this.user_name)
        }
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.println("login");
        System.out.println("register");
        input = scanner.nextLine();


            while (input.equals("login")) {

                System.out.println("username");
                String Luser = scanner.nextLine();
                System.out.println("Password");
                String Lpassword = scanner.nextLine();
                int a = count;
                login(Luser, Lpassword);
                System.out.println("");
                input = scanner.nextLine();
            }
            while (input.equals("register")) {

                System.out.println("username");
                String Ruser = scanner.nextLine();
                System.out.println("Password");
                String Rpassword = scanner.nextLine();
                users count = new users(Ruser, Rpassword);
                System.out.println("");
                input = scanner.nextLine();
            }
            while ((!input.equals("register")) || (!input.equals("login"))) {
                System.out.println("invild option, chose login or regiser!");
                input = scanner.nextLine();


        }

Answer 1

在主要方法中，我会做这样的事情：

    public static void main(String[] args) {
    Scanner scanner = new Scanner(System.in);
    System.out.println("login");
    System.out.println("register");


    while(true) {
        input = scanner.nextLine();
        switch(input) {
        case "exit":
            System.exit(0);
            break;
        case "login":
            System.out.println("username");
            String Luser = scanner.nextLine();
            System.out.println("Password");
            String Lpassword = scanner.nextLine();
            int a = count;
            login(Luser, Lpassword);
            System.out.println("");
            //              input = scanner.nextLine();
            break;
        case "register":
            System.out.println("username");
            String Ruser = scanner.nextLine();
            System.out.println("Password");
            String Rpassword = scanner.nextLine();
            Users count = new Users(Ruser, Rpassword);
            System.out.println("");
            //              input = scanner.nextLine();
            break;
        default:
            System.out.println("invild option, chose login, regiser or exit!");
            continue;
        }
    }

用户名和密码登录java项目

1 个答案: