深夜十点半（三）——我的第三个Python程序“增强版购物车”

项目要求：

1、增强版购物车是利用了文件系统，保存用户的购物列表和当前余额信息，在用户每次购物前先读取用户当前余额后再进行购买，并把购买的物品名称存到列表中；

2、用文件系统保存商品明细，不用每次都进行人工输入

程序要点：

1、文件读写操作

2、把一个格式化的文件内容读取到列表中，并对不需要的\n等信息进行处理，得到有效的格式化数据

待改进：

程序结构化不够，比较乱，后面可以函数化进行封装

'''用户入口:
    1、商品信息存在文件里
    2、已购商品，余额记录
    商家入口：
    1、可以添加商品，修改商品价格
'''
# 用户入口：
# 从文件中读取所有商品信息到字典中

f_product_list = open(r"C:\Users\Administrator\PycharmProjects\S14Week2\product", 'r')
f_shopping_list = open(r"C:\Users\Administrator\PycharmProjects\S14Week2\shoppinglist", 'r+')
product_list = []
shopping_list = []
length = 0
while True:
    product_list_temp = f_product_list.readline()
    # product_list_temp.strip()
    if product_list_temp == "" or product_list_temp == "\n":
        break
    # print("RAW Line is :",product_list_temp)
    product_list_temp = product_list_temp.strip()
    # print("Strip result is :", product_list_temp)
    product_list_temp = product_list_temp.split(",")
    # print("Split result is :",product_list_temp)
    # product_list_temp = product_list_temp.strip()
    # print(product_list_temp)
    product_list.append(product_list_temp)
# print("Final result is :",product_list)
product_list = list(product_list)
salary = 0
while True:
    shopping_list_temp = f_shopping_list.readline()
    if shopping_list_temp == "" or shopping_list_temp == "\n":
        break
    # print("RAW Line is :",product_list_temp)
    shopping_list_temp = shopping_list_temp.strip()
    # print("Strip result is :", product_list_temp)
    shopping_list_temp = shopping_list_temp.split(",")
    # print("Split result is :",product_list_temp)
    # product_list_temp = product_list_temp.strip()
    # print(product_list_temp)
    shopping_list.append(shopping_list_temp)
    salary = int(shopping_list_temp[1])

shopping_list = list(shopping_list)
# print("Final result is :",product_list)
print("Notice, this is salary:",salary)
product_list = list(product_list)
if salary == None:
    salary = input("Input your salary:")
    if salary.isdigit():
        salary = int(salary)

while True:
    for index, item in enumerate(product_list):
        print(index, item)
    choice = input("Input your choice:")
    if choice.isdigit():
        choice = int(choice)
        if choice < len(product_list) and choice >= 0:
            p_item = product_list[choice]
            print(p_item)
            if int(p_item[1]) <= salary:  # 买得起
                shopping_list.append(p_item)
                salary -= int(p_item[1])
                f_shopping_list.write(p_item[0])
                f_shopping_list.write(",")
                f_shopping_list.write(str(salary))
                f_shopping_list.write("\n")
                print("Added %s into shoppint cart, your current balance is %s" % (p_item, salary))
            else:
                print("Sorry, your money is not enough!")
        else:
            print("Product is not exist")
    elif choice == 'q':
        print("Your current balance is ", salary)
        f_shopping_list.close()
        f_product_list.close()
        break