Case1-用list写shoppingcart

#define product list
product_list = [
    ('Python book',45),
    ('iphone',5800),
    ('iwatch', 1500),
    ("bike",850),
    ("luckiin coffee",25)
]
_shop =[]

#input customer salary
salary = input("Please input your Salary!》》》：")
if salary.isdigit():
    _salary = int(salary)

    while True:
        for index,item in enumerate(product_list):  # 输入正确数字salary，打印product list
            #print(product_list.index(item),item)
            print(index,item)
            print("	")
        _choice = input("Please choice and Press 'q' to exit》》》:")

        if _choice.isdigit():
            _choice = int(_choice)

            if _choice <len(product_list ) and _choice>=0: #判读list范围
                p_item = product_list[_choice]
                if p_item[1]<=_salary: #钱够
                    _shop.append(p_item)  #添加记录到_shop 列表中
                    _salary -= p_item[1]  #扣钱
                    print("Add %s in shopping cart! Your current balance is 33[31;1m%s33[0m" %(p_item, _salary))
                else:
                    print("Not Enough Money!!!")
            else:
                print("商品 %s 不存在！！" %(_choice))

        elif _choice == 'q':
            print("------shopping list---------")
            for p in _shop:
                print (_shop)
            print("Exit!")
            exit()
        else:
            print("Invalid number!")
            break  #注意break的位置

else:
    print("Invalid Salary!!!")
    salary = input("Please input your Salary!》》》：")



###目前还有一个问题就是错误按键就退出，没有给用户重新input的机会！

作为管理员的登录和增删改查

#define the basic list
product_list = [
    ('Python book',45),
    ('iphone',5800),
    ('iwatch', 1500),
    ("bike",850),
    ("luckiin coffee",25)
]
action_list = [
    ("A","添加一条新记录"),
    ("D","删除一条记录"),
    ("U","更新商品价格"),
]
#_admin_name = input("请输入管理员用户名》》》：")
_admin_pwd = input("请输入密码》》》：")

_count = 3
while (_count <= 3) :
    if _admin_pwd == '1qaz':
        print("欢迎进入后台管理！",)

        print("-------------当前商品列表-------------")
        for index,item in enumerate(product_list):
            print(index,item)

        print("	")
        print("*****商品列表操作快捷方式*****")
        #for act_item in (action_list):
           # print(act_item)
        print(action_list)

        print("	")
        _action = input("请输入想要进行的操作》》》:")

        while _action != "q" :
            if  _action == "A" :
                _item_name = input("请输入新的商品名称>>>:")
                _item_price = input("请输入商品价格》》》：")
                if _item_price.isdigit():
                    _item_price = int(_item_price)
                    if _item_price > 0:
                        product_list.append([_item_name, _item_price])
                        for index, item in enumerate(product_list):
                            print(index, item)
                        break
                    else:
                        print("不允许价格为负数！！！")
                else:
                    print("输入的价格不是数字！")

            elif _action == "U":
                _item_no = input ("请输入商品编号》》》：")
                if _item_no.isdigit():
                    _item_no = int(_item_no)
                    if _item_no >= 0 and _item_no < len(product_list):
                        _item_price = input("请输入商品的新的价格》》》：")
                        if _item_price.isdigit():
                            _item_price = int(_item_price)
                            if _item_price > 0:
                                _item_name = product_list[_item_no][0]
                                print(_item_name)
                                print("	")
                                del product_list[_item_no]    ### udpate似乎不行，只能删一条，添一条记录了！？？？
                                product_list.append([_item_name, _item_price])
                               # product_list[_item_no][1] = _item_price ###？？？？？
                                for index, item in enumerate(product_list):
                                    print(index, item)
                                break
                            else:
                                print("不允许价格为负数！！！")
                    else:
                        print("没有该商品编号")
                    break
                else:
                    print("商品标号必须为数字！")
                break
            else:
                print("输入了错误的快捷键！")
                _action = input("请输入想要进行的操作》》》:")

        break
    else:
        _admin_pwd = input ("错误的密码，你还有%s次机会，请重新输入》》》："%(_count-1))
    _count = _count-1