本文实例讲述了Python实现的购物车功能。分享给大家供大家参考，具体如下：

这里尝试用python实现简单的购物车程序。。。

基本要求：

用户输入工资，然后打印购物菜单

用户可以不断的购买商品，直到余额不够为止

退出时打印用户已购买的商品和剩余金额。。。

代码：

#!/usr/env python

#coding:utf-8

import re,math

def get_customer_salary():

while True:

salary=raw_input('Please input your monthly salary(a positive integer):')

if __is_valid_num(salary):

return int(salary)

else:

print '[warn] Please input a valid number!'

def __is_valid_num(num):

p=re.compile(r'^\d+$')

m=p.match(num)

if m:

return True

else:

return False

def get_customer_selection():

while True:

selection=raw_input('Please enter the goods number you want to buy:')

if __is_valid_num(selection):

if __is_a_valid_selection(int(selection)):

return int(selection)

else:

print '[warn] Please enter a valid selection number'

else:

print '[warn] Please enter a valid number!\n'

def __is_a_valid_selection(selection):

if 1<=selection<=get_total_amount_of_products():

return True

else:

return False

def get_products_list():

return {'Flower':50,'Perfume':300,'Shoes':600,'Clothing':800,'Alcohol':300,

'Makeup':800,'Bike':1500,'Car':200000,'Apartment':5000000}

def get_total_amount_of_products():

return len(get_products_list())

def mapping_type_code_for_products():

return ['Flower','Perfume','Shoes','Clothing','Alcohol','Makeup','Bike','Car','Apartment']

def get_product_price(type_code):

return get_products_list()[get_product_name(type_code)]

def get_product_name(type_code):

return mapping_type_code_for_products()[type_code-1]

def get_lowest_price_of_products():

price_list=[]

for k,v in get_products_list().items():

price_list.append(v)

return min(price_list)

def get_highest_price_of_produces():

price_list=[]

for k,v in get_products_list().items():

price_list.append(v)

return max(price_list)

def still_can_buy_something(left_money):

if left_money

return False

else:

return True

def still_want_to_buy_something():

while True:

answer=raw_input('Do you still want to buy something?(y/n):')

result=is_a_valid_answer(answer)

if result=='yes':return True

if result=='no':return False

print '[warn] Please enter [yes/no] or [y/n]!\n'

def is_a_valid_answer(answer):

yes_pattern=re.compile(r'^[Yy][Ee][Ss]$|^[Yy]$')

no_pattern=re.compile(r'^[Nn][Oo]$|^[Nn]$')

if yes_pattern.match(answer):return 'yes'

if no_pattern.match(answer):return 'no'

return False

def show_shopping_list():

counter=1

for i in mapping_type_code_for_products():

print '''''(%d) %s: %s RMB''' % (counter,i+' '*(10-len(i)),str(get_products_list()[i]))

counter+=1

def is_affordable(left_money,product_price):

if left_money>=product_price:

return True

else:

return False

def time_needed_to_work_for_buying_products(salary,price):

result=float(price)/salary

return get_formatting_time(int(math.ceil(result)))

def get_formatting_time(months):

if months<12:return ('%d months' % months)

years=months/12

months=months%12

return ('%d years,%d months' % (years,months))

#主程序从这里开始

if __name__=='__main__':

salary=get_customer_salary() #获取月工资

total_money=salary

shopping_cart=[] #初始化购物车

while True:

show_shopping_list() #打印购物列表

#判断剩余资金是否能够购买列表中的最低商品

if still_can_buy_something(total_money):

selection=get_customer_selection() #获取用户需要购买的商品编号

product_price=get_product_price(selection)#获取商品的价格

product_name=get_product_name(selection)#获取商品的名称

if total_money>=product_price:

total_money-=product_price

#打印购买成功信息

print 'Congratulations!You bought a %s successfully!\n' % product_name

shopping_cart.append(product_name)#将商品加入购物车

print 'You still have %d RMB left\n' % total_money #打印剩余资金

#判断是否还想购买其他商品

if not still_want_to_buy_something():

print 'Thank you for coming!'

break

else:

#输出还需要工作多久才能购买

format_time=time_needed_to_work_for_buying_products(salary,product_price-total_money)

print 'Sorry,you can not afford this product!\n'

print "You have to work '%s' to get it!\n" % format_time

#判断是否还想购买其他商品

if not still_want_to_buy_something():break

else:

print 'Your balance is not enough and can not continue to buy anything.'

break

#打印购物车列表

print 'Now,your balance is %d,and\nYou have buy %s' % (total_money,shopping_cart)

运行效果：

希望本文所述对大家Python程序设计有所帮助。