Python购物车的实现课程

需求：

1.用户输入工资收入

2.打印商品列表

3.用户选择商品，不断的加入购物车

4.检测用户余额，直接捐款，不足提示余额不足

5.允许主动退出，退出时，打印已购商品列表

重点方法：

打印列表下标的方法：

a=[‘alex‘,‘sys‘,‘root‘,‘admin‘]

>>> for index,i in enumerate(a):
...     print(index,i)

0 alex
1 sys
2 root
3 admin

 1 #!/usr/bin/env python3
 2 # -*-conding:utf-8-**
 3 # __Author__:‘liudong‘
 4 salary=input("Input your salary:")
 5 if salary.isdigit():
 6     salary=int(salary)
 7 else:
 8     exit("Invalid data type...")
 9 welcom_msg=‘Welcome to Shopping mall‘.center(50,‘-‘)
10 print(welcom_msg)
11 exit_flag=False
12 product_list = [
13     (‘Iphone‘,5000),
14     (‘Mac Air‘,8000),
15     (‘Mac Pro‘,9000),
16     (‘XiaoMi‘,20),
17     (‘Coffe‘,30),
18     (‘Bike‘,800),
19     (‘Cloth‘,200)
20 ]
21 shop_car = []
22 while not exit_flag:
23     #for product_item in product_list:
24     #    p_name,p_price = product_item  #可选的写法
25     print("Products list".center(50,‘-‘))
26     # for p_name,p_price in product_list:
27         # print(p_name,p_price)         #由于此方法后面打印下标时，会变成2个无组，所以用下面的方法打印
28     for item in enumerate(product_list):
29         index=item[0]
30         p_name=item[1][0]
31         p_price=item[1][1]
32         print(index,‘.‘,p_name,p_price)
33     user_choice = input(‘[q=quit,c=check]What do you want to buy?:‘)
34     if user_choice.isdigit():   #肯定是选商品
35         user_choice = int(user_choice)
36         if user_choice < len(product_list):
37             p_item = product_list[user_choice]
38             if p_item[1] <= salary: #买的起
39                 shop_car.append(p_item) #放入购物车
40                 salary -= p_item[1] #扣钱
41                 print(‘Added [%s] into your shop car,your current balance is \033[31;1m[%s]\033[0m‘ %
42                   (p_item,salary))   ＃字体加颜色
43             else:
44                 print(‘Your balance is [%s],cannot afford this product..‘ %salary)
45     else:
46         if user_choice == ‘q‘ or user_choice == ‘quit‘:
47             print(‘purchased products as blew:‘.center(40,‘*‘))
48             for item in shop_car:
49                 print(item)
50             print(‘END‘.center(40,‘*‘))
51             print(‘Your balance is [%s]‘ %salary)
52             print(‘bye.‘)
53             exit_flag = True
54         elif user_choice == ‘c‘ or user_choice == ‘check‘:
55             print(‘purchased products as blew:‘.center(40, ‘*‘))
56             for item in shop_car:
57                 print(item)
58             print(‘Your balance is \033[41;1m[%s]\033[0m‘ % salary) #背景加颜色

编程的思维还要加强。。。。。