设计的银行账户管理系统，增加一个VIP账户的管理

本文主要是介绍设计的银行账户管理系统，增加一个VIP账户的管理，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

程序功能如下：
1.当单击“创建VIP账户”按钮时，显示如图5-11所示的信息，其中卡号为随机生成的一个在500000到999999之间的一个值，余额初始化为10000元。
2.在“取款”文本框中输入取款金额后，单击“取款”按钮，显示如图5-12所示的信息。如果余额不足，VIP用户可以透支1000元，如取款800，而余额是400，则显示如图5-13所示的信息。如透支超过1000元，如取款1600，而余额是400，则显示如图5-14所示的信息。
3.要求：在上机实验4-3的基础上，通过继承和多态实现上述操作。
C#界面如下：
在这里插入图片描述

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;namespace WindowsFormsApp8
{public partial class Form1 : Form{public Form1(){InitializeComponent();}Account account;    //定义一个账户类对象private void btnCrtSavingAc_Click(object sender, EventArgs e){account = new Account();//实例化储蓄卡用户账户string message = string.Format("创建账户成功，用户卡号为：{0}", account.CreditNo);lblShow.Text = "\n" + message +"\n";}private void btnWithDraw_Click(object sender, EventArgs e)//取款{string message;if (account == null)message = "请先创建账户!";       //帐户不存在else if (txtWithDraw.Text == "")message = "请输入取款金额";    //未输入取款金额else{decimal money = decimal.Parse(txtWithDraw.Text);account.WithDraw(money, out message);       //message存放取款的金额信息}lblShow.Text = "\n" + message + "\n";}private void btnDeposit_Click(object sender, EventArgs e){string message;if (account == null)message = "请先创建账户!";    //帐户是否存在else if (txtDeposit.Text == "")message = "请输入存款金额";     //输入存款金额else{decimal money = decimal.Parse(txtDeposit.Text);account.Deposit(money, out message);}lblShow.Text = "\n" + message + "\n";//输出存款金额}private void button2_Click(object sender, EventArgs e)//查询余额操作{string message;if (account == null)message = "请先创建账户!";else{account.show( out message);}lblShow.Text = "\n" + message + "\n";    //输出余额}private void btnCrtVipAc_Click(object sender, EventArgs e){account = new VipAccount();        //实例化VIP用户账户int accountNo = account.CreditNo;string message = string.Format("创建VIP账户成功，用户卡号为：{0}",accountNo);lblShow.Text = "\n" + message + "\n";}}public class Account
{//成员字段的属性改为protectedprotected int creditNo;protected decimal balance;public Account(){Random r = new Random();creditNo = r.Next(100000, 500000);  //产生一个100000到500000的随机数balance = 100;  //余额初始化为100}public decimal Balance //只读属性，读取余额{get { return this.balance; }}public int CreditNo    //只读属性，读取储蓄卡号{get { return this.creditNo; }}//改写Account类的WithDraw为虚方法public virtual bool WithDraw(decimal money, out string message)    //取款{if (money < 0)  //取款金额小于0{message = "操作失败：\n输入金额不正确！";return false;}else if (balance >= money)   //取款金额大于余额{balance -= money;message = "操作成功！\n取款" + money + "元";return true;}else{message = "操作失败！\n余额不足！";return false;}}public bool Deposit(decimal money, out string message){if (money < 0){message = "操作失败：\n输入金额不正确！";return false;}else{balance += money;message = "操作成功！\n存款" + money + "元";return true;}}public bool show(out string message){message = "您的余额为：\n" + balance + "元";return true;}}public class VipAccount : Account{public VipAccount(){Random r = new Random();creditNo = r.Next(500000, 1000000);balance = 10000;}public override bool WithDraw(decimal money, out string message){if (money < 0){message = "操作失败：\n输入金额不正确！";return false;}else if (balance >= money){balance -= money;message = "操作成功！\n取款" + money + "元";return true;}else if (balance+1000 >= money)  //取款金额大于于可透支余额{balance -= money;message = "操作成功！\n取款" + money + "元,透支"+(-balance)+"元";return true;}else{message = "操作失败！\n余额不足！";return false;}}}
}