报名系统

Question

我正在尝试用我在网上学到的东西来制作一个项目。

public static void main(String[]args){

    int balance, payment;


    balance = 11310;

    String new1 = "new";

    String old = "old";

    String partial = "partial";

    String full = "full";

    String no = "no";

    String yes = "yes";

    String First = "first year second sem";

    String Second = "second year first sem";

    String Third = "second year second sem";

    System.out.print("\nEnter Name: ");

    Scanner st = new Scanner(System.in);

    String name = st.nextLine();

    System.out.print("\nOld Student or New Student: ");

    String student = st.nextLine();

    if(student.equalsIgnoreCase(new1)){

        System.out.print("\nGreetings, "+name);

        System.out.print("\nPlease fill out our Registration Form.");

        System.out.print("\nThank you!");

    try {

     if(Desktop.isDesktopSupported()) {

        Desktop.getDesktop().open(new File("C:\\Users\\toshiba-1\\Desktop\\Regform1styr.2ndsem - Copy.docx"));

     }

    }

     catch (IOException ioe) {

     ioe.printStackTrace();

    }

    return;

    }


    System.out.print("\nGreetings, "+name);

    System.out.print("\nWould you want to enroll for a new semester? ");

    String enroll = st.nextLine();

    if(enroll.equalsIgnoreCase(no))
    {
     System.out.print("\nThank you!");

     return;
    }

    if(enroll.equalsIgnoreCase(yes))
    {

    }

    System.out.print("\nWhich Semester? ");

    String semester = st.nextLine();

    if(semester.equalsIgnoreCase(First)) // My error started here.
    {
    }

    else if(semester.equalsIgnoreCase(Second))
    {
    }

    else if(semester.equalsIgnoreCase(Third))
    {
    }

    else
    {
     System.out.print("\nPlease choose a semester.");
    }

    System.out.print("\nThe Enrollment fee for this Semester is: "+ balance);

    System.out.print("\nChoose your Payment term(Partial/Full): ");

    String term = st.nextLine();

    if(term.equalsIgnoreCase(partial))
     {

        System.out.print("\nHow much would you like to pay for this semester: ");

        Scanner in = new Scanner(System.in);

        payment = in.nextInt();


        balance = balance - payment;

        System.out.print("\nYour Balance is: SR"+ balance);

        if(balance > payment){

            System.out.print("\nYou have remaining balance of: SR" + balance);

        }else if(balance == payment){

            System.out.print("\nYou are already paid");

        }

     }



}
}

当用户选择三个字符串时，我遇到了麻烦。我或者尝试了这组代码。

    if(semester.equalsIgnoreCase(First))
    {
     System.out.print("\nPlease choose a semester.");
    }

    System.out.print("\nThe Enrollment fee for this Semester is: "+ balance);

    System.out.print("\nChoose your Payment term(Partial/Full): ");

    String term = st.nextLine();

    if(term.equalsIgnoreCase(partial))
     {

        System.out.print("\nHow much would you like to pay for this semester: ");

        Scanner in = new Scanner(System.in);

        payment = in.nextInt();


        balance = balance - payment;

        System.out.print("\nYour Balance is: SR"+ balance);

        if(balance > payment){

            System.out.print("\nYou have remaining balance of: SR" + balance);

        }else if(balance == payment){

            System.out.print("\nYou are already paid");
    }

    else if(semester.equalsIgnoreCase(Second))
    {
     System.out.print("\nPlease choose a semester.");
    }

    System.out.print("\nThe Enrollment fee for this Semester is: "+ balance);

    System.out.print("\nChoose your Payment term(Partial/Full): ");

    String term = st.nextLine();

    if(term.equalsIgnoreCase(partial))
     {

        System.out.print("\nHow much would you like to pay for this semester: ");

        Scanner in = new Scanner(System.in);

        payment = in.nextInt();


        balance = balance - payment;

        System.out.print("\nYour Balance is: SR"+ balance);

        if(balance > payment){

            System.out.print("\nYou have remaining balance of: SR" + balance);

        }else if(balance == payment){

            System.out.print("\nYou are already paid");
    }

    else if(semester.equalsIgnoreCase(Third))
    {
     System.out.print("\nPlease choose a semester.");
    }

    System.out.print("\nThe Enrollment fee for this Semester is: "+ balance);

    System.out.print("\nChoose your Payment term(Partial/Full): ");

    String term = st.nextLine();

    if(term.equalsIgnoreCase(partial))
     {

        System.out.print("\nHow much would you like to pay for this semester: ");

        Scanner in = new Scanner(System.in);

        payment = in.nextInt();


        balance = balance - payment;

        System.out.print("\nYour Balance is: SR"+ balance);

        if(balance > payment){

            System.out.print("\nYou have remaining balance of: SR" + balance);

        }else if(balance == payment){

            System.out.print("\nYou are already paid");
    }

    else
    {
System.out.print("Please choose a semester.");

return;
      }

但结果仍然在混淆。请帮帮我。

Answer 1

如果您希望代码正常工作，则需要为问题添加循环：

System.out.print("\nWhich Semester? ");
// changed code!!
while(true){
    String semester = st.nextLine();
    if(semester.equalsIgnoreCase(First)){
        break;
    }else if(semester.equalsIgnoreCase(Second)){
        break;
    }else if(semester.equalsIgnoreCase(Third)){
        break;
    }else{
        System.out.print("\nPlease choose a semester.");
    }
}
//end of chaged code!!
System.out.print("\nThe Enrollment fee for this Semester is: "+ balance);

然而，基于像你这样的字符串程序流控制是非常糟糕的。