day01-homework_购物车程序

#usr/bin/env/python3
# -*- coding: utf-8 -*-

#编写购物车

class account(object):
    def __init__(self):
        self.cash=50000.0
        self.__stocklist=[]
    def get(self):
        return  self.cash
    def add(self,value):
        self.cash+=value
    def minus(self,value):
        self.cash-=value
    def refresh_account(self):
        print('***Account Information:')
        print('***Your Cash:%10.2f'%self.cash)
        index=0
        for item in self.__stocklist:
            index+=1
            print('***Your Stock%d\tName:%s\tPrice:%10.2f'%(index,item[0],item[1]))
    def add_stock(self,stock_name,stock_price):
        self.__stocklist.append([stock_name,stock_price])

class shopping(object):
    def __init__(self):
        pass
        self.__stock={
            'Iphone7'   :[2,5000],
            'MacPro'    :[2,15000],
            'Kindle'    :[5,1000],
            'Bike'      :[2,2000],
        }
    def list_items(self):
        print('***Number\tItems:\tStock:\tPrice:***')
        i=0
        for items in list(self.__stock.items()):
            print("***%d\t%s\t\t%d\t\t%10.2f"%(i,items[0],items[1][0],items[1][1]))
            i+=1
    def waiting(self,usr_account):
        while True:
            self.list_items()
            usr_order=input('***Which one do you want to buy?Enter Number:')
            #退出机制
            if(usr_order in ['q','quit','exit']):
                print('Let\'s check your account again.')
                usr_account.refresh_account()
                print('Thank you very much. Have a nice day. Bye.')
                exit()
            #输入检查
            try:
                OrderNum=int(usr_order)
                if OrderNum>=len(self.__stock) or OrderNum<0:
                    print('***Input Error, your input is not in range.')
                    continue
            except ValueError:
                print('***Input Error, You can only input an integer.')
                continue
            #判断账户余额是否足够
            cur_stock=list(self.__stock.items())[OrderNum]
            if cur_stock[1][1]>usr_account.get():
                print('***You don\'t have enough money.Please check your account.')
                continue
            else:
                usr_account.minus(cur_stock[1][1])
                usr_account.add_stock(cur_stock[0],cur_stock[1][1])
                print('***Pay Sucess.\n***You spent %10.2f RMB to buy a %s'%(cur_stock[1][1],cur_stock[0]))
                usr_account.refresh_account()
                self.__stock[cur_stock[0]][0]=self.__stock[cur_stock[0]][0]-1
                if self.__stock[cur_stock[0]][0]<=0:
                    del self.__stock[cur_stock[0]]
                    if(self.__stock=={}):
                        print('Ooooooops,you bought the shop out. Shop Closed.Bye.')
                        usr_account.refresh_account()
                        exit()


shop=shopping()
cur_usr=account()
shop.waiting(cur_usr)