java - 银行账户程序: Rejecting Deposit or Withdrawal

Question

我一直在致力于制作一个模拟银行交易的程序。我必须询问用户是否要存款、取款或转账。现在我正在研究帐户的存款和取款选项。

当用户选择一项交易(例如存款)并输入一个数字时，我让程序询问“您想继续此交易吗？显然，如果是，程序将继续交易，如果否，它不会存入用户输入的号码。

我的问题是，我不知道我需要在 no 选项中添加什么。我不知道拒绝交易是否意味着我必须退出循环或者什么，但目前如果我点击“否”，交易仍然会进行。下面是当我输入交易但不想继续时发生的情况的视觉效果:

下面是我的整个代码。我不知道该放什么的代码部分有**这可能对我的组织没有帮助，对此我深感抱歉!

import java.util.Scanner;

public class BankTransactions {


public static void main(String[] args) {

    Scanner scan = new Scanner(System.in);
    int num;
    double balance = 0;
    double checkingBalance= 0, savingsBalance =0;

    do {

        double amount;

        System.out.println("------------------------");
        System.out.println("Select a Transaction by typing number");
        System.out.println("1. Deposit");
        System.out.println("2. Withdrawal");
        System.out.println("3. Balance");
        System.out.println("4. Exit");
        System.out.println("------------------------");
        num = scan.nextInt();


        if (num == 1) { //if DEPOSIT is selected

            //ask to deposit from checking or savings
            System.out.println("------------------------");
            System.out.println("Would you like to deposit in checking or savings?");
                System.out.println("1. Checking");
                System.out.println("2. Savings");
            System.out.println("------------------------");
                num = scan.nextInt();

                if (num == 1) { //if CHECKING is selected
                    //enter amount to be deposited
                    System.out.println("------------------------");
                    System.out.println("Enter amount to deposit in checking account: ");
                    System.out.println("------------------------");
                    amount = scan.nextDouble();

                    //ask if they want to continue with transaction
                    System.out.println("------------------------");
                    System.out.println("Would you like to continue this transaction?");
                        System.out.println("1. Yes");
                        System.out.println("2. No");
                    System.out.println("------------------------");
                        num = scan.nextInt();

                    // Add the amount to the checking balance
                    checkingBalance += amount;
                    System.out.println("------------------------");
                    System.out.println("Your checking account's balance is " + checkingBalance);
                    System.out.println("------------------------");

                } else if (num == 2) { //if SAVINGS is selected
                    //enter amount to be deposited
                    System.out.println("------------------------");
                    System.out.println("Enter amount to deposit in savings account: ");
                    System.out.println("------------------------");
                    amount = scan.nextDouble();

                    //ask if they want to continue with transaction
                    System.out.println("------------------------");
                    System.out.println("Would you like to continue this transaction?");
                        System.out.println("1. Yes");
                        System.out.println("2. No");
                    System.out.println("------------------------");
                        num = scan.nextInt();

                        if (num == 1) {
                            // Add the amount entered to the savings balance
                            savingsBalance += amount;
                            System.out.println("------------------------");
                            System.out.println("Your savings account's balance is " + savingsBalance);
                            System.out.println("------------------------");
                        **} else if (num == 2) {
                            //EMPTY NEEDS CODE
                        }**
                }


        } else if (num == 2) { //if withdrawal is selected

            //ask to withdrawal from checking or savings
            System.out.println("------------------------");
            System.out.println("Would you like to withdrawal from checking or savings?");
                System.out.println("1. Checking");
                System.out.println("2. Savings");
            System.out.println("------------------------");
                num = scan.nextInt();

                if (num == 1) { //if checking is selected
                    //enter amount to be withdrawn
                    System.out.println("------------------------");
                    System.out.println("Enter amount to withdrawal: ");
                    System.out.println("------------------------");
                    amount = scan.nextDouble();

                    //ask if they want to continue with transaction
                    System.out.println("------------------------");
                    System.out.println("Would you like to continue this transaction?");
                        System.out.println("1. Yes");
                        System.out.println("2. No");
                    System.out.println("------------------------");
                        num = scan.nextInt();

                        if (num == 1) { //if you say yes to continuing
                            // Remove the amount from the balance
                            checkingBalance -= amount;
                            System.out.println("------------------------");
                            System.out.println("Your checking account's balance is " + checkingBalance);
                            System.out.println("------------------------");
                        } else if (num == 2) { //if you say no to continuing
                            //Do not remove amount from savings balance
                            //EMPTY NEEDS CODE
                        }                               

                } else if (num == 2) { //if savings is selected
                    //enter amount to be withdrawn
                    System.out.println("------------------------");
                    System.out.println("Enter amount to withdrawal: ");
                    System.out.println("------------------------");
                    amount = scan.nextDouble();

                    //ask if they want to continue with transaction
                    System.out.println("------------------------");
                    System.out.println("Would you like to continue this transaction?");
                        System.out.println("1. Yes");
                        System.out.println("2. No");
                    System.out.println("------------------------");
                        num = scan.nextInt();

                        if (num == 1) { //if you say yes to continuing
                            // Remove the amount from the savings balance
                            savingsBalance -= amount;
                            System.out.println("------------------------");
                            System.out.println("Your savings account's balance is " + savingsBalance);
                            System.out.println("------------------------");
                        } else if (num == 2) { //if you say no to continuing
                            //Do not remove amount from savings balance
                            //EMPTY NEEDS CODE
                        }
                }


        } else if (num == 3) { //if balance is selected

            //ask to see balance of checking or savings
            System.out.println("------------------------");
            System.out.println("Your Checking balance is " + checkingBalance);
            System.out.println("Your Savings balance is " + savingsBalance);
            System.out.println("------------------------");
                num = scan.nextInt();

                //needs to return to transaction options
        }



    } while (num != 4);

    System.out.println("------------------------");
    System.out.println("Good Bye!");
    System.out.println("------------------------");

}

}

我被困住了，我想弄清楚。请不要发布更正后的整个代码。我想自己修复并学习!

Answer 1

交易仍会进行检查，但不会进行储蓄。

原因如下:

if (num == 1) { //if CHECKING is selected
                    //enter amount to be deposited
                    System.out.println("------------------------");
                    System.out.println("Enter amount to deposit in checking account: ");
                    System.out.println("------------------------");
                    amount = scan.nextDouble();

                    //ask if they want to continue with transaction
                    System.out.println("------------------------");
                    System.out.println("Would you like to continue this transaction?");
                        System.out.println("1. Yes");
                        System.out.println("2. No");
                    System.out.println("------------------------");
                        num = scan.nextInt();

                    // Add the amount to the checking balance
                    checkingBalance += amount;
                    System.out.println("------------------------");
                    System.out.println("Your checking account's balance is " + checkingBalance);
                    System.out.println("------------------------");

                } else if (num == 2) { //if SAVINGS is selected
                    //enter amount to be deposited
                    System.out.println("------------------------");
                    System.out.println("Enter amount to deposit in savings account: ");
                    System.out.println("------------------------");
                    amount = scan.nextDouble();

                    //ask if they want to continue with transaction
                    System.out.println("------------------------");
                    System.out.println("Would you like to continue this transaction?");
                        System.out.println("1. Yes");
                        System.out.println("2. No");
                    System.out.println("------------------------");
                        num = scan.nextInt();

                        if (num == 1) {
                            // Add the amount entered to the savings balance
                            savingsBalance += amount;
                            System.out.println("------------------------");
                            System.out.println("Your savings account's balance is " + savingsBalance);
                            System.out.println("------------------------");
                        **} else if (num == 2) {
                            //EMPTY NEEDS CODE
                        }**
                }

注意“num = scan.nextInt();”之后的区别两种情况下都行吗？在第一种情况下，您指示它继续并添加，无论输入如何，在第二种情况下，您有一个 if/else 语句，仅当用户输入 1 时才会添加它，如果他输入 2 ，您将什么也不做。

至于你关于在除 1 或 2 之外的任何其他选项的情况下该怎么做的问题。我会使用 if 语句来检查 num 是否为 1，而不使用 else 语句，因此如果输入任何其他选项，它会又回到起点。 (但是如果你坚持 2 是“否”，你可以使用 else if(num != 2){System.out.println("Invalid Option. Going to the begin";}