java - 将记录存储在 for 循环数组中并显示它们

Question

我正在尝试创建一个程序来生成机票，然后它会询问用户是否想查看乘客列表。

我遇到的困难是，每个用户输入详细信息后，他们都必须添加到乘客列表中。 因此，如果用户 1 输入他的详细信息，并且必须询问他们是否想要查看乘客列表(到目前为止，乘客列表下只有一条记录)，那么当用户 2 输入他的详细信息时，它必须询问用户是否想要查看乘客列表。乘客列表和 User2 详细信息必须添加到乘客列表中(因此乘客列表下将有 2 条记录)，依此类推。

请协助。

public class Question12 {

    public static void main(String[] args) {
               double random = Math.random()* 69 + 1;
               String q;
        Scanner in = new Scanner(System.in);
        String[][] PlaneTicket = new String[3][3];

       for (int row = 0; row < 67; row++) {


           System.out.print("Enter name:");        
           PlaneTicket[row][0] = in.next();

           System.out.print("Enter surname: ");
           PlaneTicket[row][1] = in.next();


           System.out.print("Enter a ID: ");
           PlaneTicket[row][2] = in.next();

           System.out.println("************Airport**********");
           System.out.println("Seat number: " +  Math.round(random));
           System.out.println("Name: " + PlaneTicket[row][0]);
           System.out.println("Surname: " + PlaneTicket[row][1]);
           System.out.println("ID: " + PlaneTicket[row][2]);
           System.out.println("*****************************");

           System.out.println("Do you want to view the passanger list: " + "(Yes/No)");
           q = in.next();

          if ("Yes".equals(q))  {
           System.out.println("Name     Surname     ID     Seat Number");
           System.out.println("----------------------------------------");
           System.out.println(PlaneTicket[row][0]+"    "+PlaneTicket[row][1]+"      "+PlaneTicket[row][2]+ "    "+ Math.round(random));   

Answer 1

如果您只想打印到目前为止输入的所有值，您可以这样做:

System.out.println("Name     Surname     ID     Seat Number");
System.out.println("----------------------------------------");

for (int k = 0; k <= row; k++) {   
    System.out.println(PlaneTicket[k][0] + "    " + PlaneTicket[k][1] + "      " + PlaneTicket[k][2] + "    " + Math.round(random));
}

这能回答你的问题吗？

一些评论:

• 您必须修复数组大小(如评论中所述):String[][] PlaneTicket = new String[67][3];
• 您应该创建一个类PassengerTicket，这将有助于使您的代码更具可读性(并且更加面向对象)
• 您应该重新设计代码，以利用不同操作的方法(添加、打印……)
• 您的输出应该被格式化(例如，使用 String.format)
• 您应该看看Collections，这将使您的代码更具可读性并且可能更易于维护，即 https://docs.oracle.com/javase/7/docs/api/java/util/Collections.html , https://docs.oracle.com/javase/7/docs/api/java/util/ArrayList.html

这是您的主要方法，并进行了一些修复，如上所述，请进行一些重新设计(请参阅我的评论):

public static void main(String[] args) {
    final int maxPassengers = 67;

    double random = Math.random() * 69 + 1;
    String q;
    Scanner in = new Scanner(System.in);
    String[][] PlaneTicket = new String[maxPassengers][4];

    for (int row = 0; row < maxPassengers; row++) {
        System.out.print("Enter name:");
        PlaneTicket[row][0] = in.next();

        System.out.print("Enter surname: ");
        PlaneTicket[row][1] = in.next();

        System.out.print("Enter a ID: ");
        PlaneTicket[row][2] = in.next();

        // you should keep the SeatNumber
        PlaneTicket[row][3] = String.valueOf(Math.round(random));

        System.out.println("************Airport**********");
        System.out.println("Seat number: " + PlaneTicket[row][3]);
        System.out.println("Name: " + PlaneTicket[row][0]);
        System.out.println("Surname: " + PlaneTicket[row][1]);
        System.out.println("ID: " + PlaneTicket[row][2]);
        System.out.println("*****************************");

        System.out.println("Do you want to view the passanger list: " + "(Yes/No)");
        q = in.next();

        if ("Yes".equalsIgnoreCase(q) || "y".equalsIgnoreCase(q)) {
            System.out.println("Name     Surname     ID     Seat Number");
            System.out.println("----------------------------------------");

            for (int k = 0; k <= row; k++) {
                System.out.println(PlaneTicket[k][0] + "    " + PlaneTicket[k][1] + "      " + PlaneTicket[k][2] + "    " + PlaneTicket[row][3]);
            }
        }
    }
}