demo4.py

# -*- coding:utf-8 -*-
"""
# 作业四：
#
# 要求用户输入总资产，例如：2000
# 显示商品列表，让用户根据序号选择商品，加入购物车
# 购买，如果商品总额大于总资产，提示账户余额不足，否则，购买成功。
# 附加：可充值、某商品移除购物车
"""

goods = [
    {"name": "电脑", "price": 1999},
    {"name": "鼠标", "price": 10},
    {"name": "游艇", "price": 20},
    {"name": "美女", "price": 998},
]

while True:

    total_inp = input("请输入您的总资产：")
    if total_inp == "":

        print("指令输入有误，请重新选择！")
        continue
    else:
        total = int(total_inp)
        break

cart = []  # 购物车
cart_sum = 0  # 总价格
cart_size = 0  # 总数量
while True:

    print("=======商品栏=======")
    for i in range(0, len(goods)):
        temp = goods[i].get('name')
        print(i+1,temp)
    print("0 结束购物，查看购物车")
    print("===================")
    opt_inp = input("请选择：")
    if opt_inp == "":

        print("指令输入有误，请重新选择！")
        continue
    else:
        opt = int(opt_inp)
    if opt == 0:
        while True:

            print("=======购物车=======")
            print("总资产：", total)
            print("总价格：", cart_sum)
            print("总数量：", cart_size)
            for i in range(0, len(cart)):
                print(i + 1, cart[i].get('name'), "价格", cart[i].get('price'))
            print("8  [返回]")
            print("9  [充值]")
            print("0  [结算]")
            print("删除商品请输入商品对应序号")
            print("===================")

            opt2_inp = input("请选择：")
            if opt2_inp == "":

                print("指令输入有误，请重新选择！")
                continue
            else:
                opt2 = int(opt2_inp)

            # 返回项
            if opt2 == 8:
                break

            # 充值项
            elif opt2 == 9:
                top_up = int(input("请输入要充值的金额数："))
                total += top_up
                print("充值成功")
                continue

            # 结算项
            elif opt2 == 0:
                if cart_sum > total:

                    print("您的资产余额不足，还差", cart_sum - total, "请充值后重新结算")
                    continue
                else:
                    if cart_sum == 0:
                        #
                        print("您尚未选购商品，请先选择商品并加入购物车！")
                        break
                    else:
                        #
                        print("已支付", cart_sum, "元，购买成功！")
                        total -= cart_sum
                        cart = []
                        cart_size = 0
                        cart_sum = 0
                        continue

            # 删除商品项
            else:
                if opt2 > cart_size:
                    # 
                    print("指令输入有误，请重新选择！")
                    continue
                else:

                    print("已删除价格为[", cart[opt2 - 1].get('price'), "]的商品[", cart[opt2 - 1].get('name'), "]")
                    cart_size -= 1
                    cart_sum -= cart[opt2 - 1].get('price')
                    del cart[opt2 - 1]
                    continue

    # 添加商品到购物车
    else:
        if opt > len(goods) or opt == "":

            print("指令输入有误，请重新选择！")
            continue
        else:

            print("已添加价格为[", goods[opt - 1].get('price'), "]的商品[", goods[opt - 1].get('name'), "]到购物车")
            cart.append(goods[opt - 1])
            cart_size += 1
            cart_sum += goods[opt - 1].get('price')