python#父与子的编程之旅#第十四章

1. 为BankAccount 建立一个类定义。它应该有一些属性，包括账户名（一个字
符串）、账号（一个字符串或整数）和余额（一个浮点数），另外还要有一些
方法显示余额、存钱和取钱。

class BankAccount:
    def __init__(self,account,account_id,account_balance):
        self.account = account
        self.account_id = account_id
        self.account_balance =account_balance

    def getBalance(self):#显示余额
        balance = self.account_balance
        return balance
        print("余额为",balance)

    def saveMoney(self,money):#显示存钱
        self.account_balance = self.account_balance + money
        print("存入",money)
        print("现在账户余额",self.account_balance)

    def withDraw(self,getmoney):
        surplus = self.account_balance - getmoney
        if getmoney>self.account_balance:
            print("余额不足")
        else:
            print("你已取出：",getmoney,"元")
            print("您的",self.account_id,"账户剩余：",surplus)
　　　　　　　self.account_balance =surplus    #如果未对self.account_balance赋上修改取出后的值，则可能导致上次扣除后余额不更新

　　　　#可以取消赋值
　　　　#else:
　　　　#　　self.account_balance = self.account_balance -getmoey
　　　　#   print("你已取出",getmoney,"元")
　　　　#   print("您的"，self.account_id,"账户剩余"，self.account_balance)

"""看过一些文章说的是把初始的账户余额定为0的，而我这个设置为参数，输入余额"""

a = BankAccount("叶","yescarf",18)

a.saveMoney(100)
a.withDraw(150)

a.withDraw(12)

2. 建立一个可以挣利息的类，名为InterestAccount。这应当是BankAccount
的一个子类（所以会继承BankAccount 的属性和方法）。InterestAccount
还应当有一个对应利息率的属性，另外有一个方法来增加利息。为了力求简
单，假设每年会调用一次addInterest() 方法计算利息并更新余额。

class BankAccount:
    def __init__(self,account,account_id,account_balance):
        self.account = account
        self.account_id = account_id
        self.account_balance =account_balance

    def getBalance(self):#显示余额
        balance = self.account_balance
        return balance
        print("余额为",balance)

    def saveMoney(self,money):#显示存钱
        self.account_balance = self.account_balance + money
        print("存入",money)
        print("现在账户余额",self.account_balance)

    def withDraw(self,getmoney):
        surplus = self.account_balance - getmoney
        if getmoney>self.account_balance:
            print("余额不足")
        else:
            print("你已取出：",getmoney,"元")
            print("您的",self.account_id,"账户剩余：",surplus)
        self.account_balance =surplus #如果未对self.account_balance赋上修改取出后的值，则可能导致依旧按元先账户余额计算结果，导致错误

"""a = BankAccount("叶","yescarf",18)

a.saveMoney(100)
a.withDraw(150)

a.withDraw(12)"""

class InterestAccount(BankAccount):
    def __init__(self,rate):
        BankAccount.__init__(self,"weimiaomiao", 123456,0)#init继承
        self.rate = rate

    def addInterest(self):
        interest =self.account_balance *self.rate
        surplus = interest+self.account_balance
        print("利息为",interest)
        print("结余余额为",surplus)
b= InterestAccount(0.2)
b.saveMoney(100)
b.saveMoney()
b.withDraw(20.5)
b.withDraw(50)
b.addInterest()