package 上機練習; import java.util.Scanner; public class A04class { double Money = 0; public double showA() { return Money; } public void showB(double money) { Money += money; System.out.println("當前餘額:" + Money); } public void showC(double money2) { if (money2 > Money) { System.out.println("餘額不足!你當前稱呼餘額" + Money); } else { Money -= money2; System.out.println("取款成功"); System.out.println("當前餘額:" + Money); } } } package 上機練習; import java.util.Scanner; public class A04 { public static void main(String[] args) { // TODO Auto-generated method stub Scanner in = new Scanner(System.in); A04class A04 = new A04class(); boolean con = true; while (con) { System.out.println("\t1.存 款 \t2.取 款 \t3.退 出"); System.out.print("請選擇您要辦理的業務:"); int choice = in.nextInt(); switch (choice) { case 1: System.out.print("請輸入存款金額:"); double Money = in.nextDouble(); A04.showB(Money); System.out.println("存款成功"); break; case 2: System.out.print("請輸入取款金額:"); double Money2=in.nextInt(); A04.showC(Money2); break; case 3: System.out.println("謝謝使用!"); con=false; break; default: System.out.println("輸入有誤!從新輸入:"); A04 A=new A04(); A.main(null); break; } } } }