前几天由于过敏躺尸了两周，感觉都快废了。想要再次跨考计算机的计划遭到了家人的激烈反对。最后不了了之，对本行业越来越失望，希望通过这三年的自学成功跳行。
这次作业多学了好多东西才做出来深感码力不足，if-else循环用的太多了。即便刚学了函数，还是不知道使用函数精简代码的套路。希望后续课程有作补充。
作业要求
一、购物模式：
1.顾客输入薪水后打印商品列表
2.顾客可以根据商品列表的下标购买商品
3.若薪水不足支付购买的商品会报错
4.顾客退出的时候打印购买的商品列表并显示余额退出
二、管理员模式
1.在输入薪水的时候输入:administrator即可进入管理员模式
2.可根据商品的编号修改商品名称、价格
3.可添加新的商品
4.最后把修改后的商品数据写入商品文本中
前期准备工作
在源码同一文件夹下创建一商品文本内容如下：
源代码
1 #author : negu 2 # -*- coding: utf-8 -*- 3 def list_loop(list):#展示商品列表的函数 4 for index,i in enumerate(list):#把每项的下标取出来 5 if index == 0: 6 continue 7 print(index,i) 8 view_list = ['blank']#商品列表，第一项占位，让商品序号从1开始。 9 with open('goods','r+',encoding='utf-8') as f:#如上一次作业一样，把文件导入列表 10 for line in f: 11 goodname = line.strip().split(':')[0] 12 goodprice = line.strip().split(':')[1] 13 view_list.append([goodname,goodprice])#以子列表形式导入列表 14 salary = input("please input your salary: ") 15 if salary == 'administrator':#进入管理员模式 16 while True: 17 list_loop(view_list) 18 choose = input("1.change the item name,2.chage the item price,3.add new item,else:quit: ") 19 if choose == '1': 20 choose_1 = input("which item's name do you want to chage?: ")#想改名字的商品的编号 21 if choose_1.isdigit(): 22 choose_1 = int(choose_1) 23 if choose_1 <= len(view_list) and choose_1 >= 0 :#判断是否在列表中，重复代码下次多次出现 24 p_1 = view_list[choose_1] 25 choose_1_1 = input('input its new name: ')#新名字 26 p_1[0] = choose_1_1 27 else : 28 print('invalid number') 29 continue 30 else : 31 print('invalid number') 32 continue 33 elif choose == '2': 34 choose_2 = input("which item's price do you want to change?: ")#想改价格的商品的编号 35 if choose_2.isdigit(): 36 choose_2 = int(choose_2) 37 if choose_2 <= len(view_list) and choose_2 >= 0 : 38 p_1 = view_list[choose_2] 39 choose_2_2 = input('input its new price: ')#新价格 40 else: 41 print('invalid number') 42 continue 43 else: 44 print('invalid number') 45 continue 46 p_1[1] = choose_2_2 47 elif choose == '3':#添加新商品 48 temporary_name = input("input your good's name: ") 49 temporary_price = input("input your good's price: ") 50 if temporary_price.isdigit(): 51 pass 52 else: 53 print('invalid number') 54 continue 55 view_list.append([temporary_name,temporary_price])#临时列表追加新商品 56 elif choose == 'q': 57 with open('goods','w+',encoding='utf-8') as fi : 58 for i in view_list: 59 if i == 'blank': 60 continue 61 s = '%s:%s '%(i[0],i[1]) 62 fi.write(s)#将临时列表的商品写入文本中 63 exit() 64 else : 65 print('invalid number') 66 continue 67 elif salary.isdigit(): 68 salary = int(salary) 69 elif not salary.isdigit(): 70 print('invalid input') 71 exit() 72 cart = [] 73 while True : 74 for index,i in enumerate(view_list):#把每项的下标取出来 75 if index == 0: 76 continue 77 print(index,i) 78 serial_number = input(" please input item number: ") 79 if serial_number.isdigit(): 80 serial_number = int(serial_number) 81 if serial_number <= len(view_list) and serial_number >= 0 : 82 p_i = view_list[serial_number] 83 if p_i[1].isdigit(): 84 p_i[1] = int(p_i[1]) 85 if p_i[1] <= salary: #买得起 86 cart.append(p_i[0]) 87 salary -= p_i[1] 88 print("added %s into shopping cart,your current balance is %s"%(p_i,salary)) 89 else : print(" 33[41;1myour current balance is not enough. 33[0m") 90 #len函数返回的是列表的长度 91 else: 92 print("商品不存在") 93 elif serial_number == 'q' : 94 print("您已购买的产品有:",cart) 95 exit() 96 else: 97 print("invalid input") 98 continue
测试方法
一、管理员模式 1.进入管理员模式将banana改成watermelon，价格改成25.
2.加一个新的商品pear，价格8
二、顾客模式
1.输入2000薪水随便买些东西
2.输入20薪水买爆报错
3.输入'fuck off'看一下系统的识别能力
结果
一、
1.输出结果：
please input your salary: administrator 1 ['banana', '10'] 2 ['flowers', '30'] 3 ['bottle', '15'] 4 ['flag', '11'] 1.change the item name,2.chage the item price,3.add new item,else:quit: 1 which item's name do you want to chage?: 1 input its new name: watermelon 1 ['watermelon', '10'] 2 ['flowers', '30'] 3 ['bottle', '15'] 4 ['flag', '11'] 1.change the item name,2.chage the item price,3.add new item,else:quit: 2 which item's price do you want to change?: 1 input its new price: 25 1 ['watermelon', '25'] 2 ['flowers', '30'] 3 ['bottle', '15'] 4 ['flag', '11'] 1.change the item name,2.chage the item price,3.add new item,else:quit: 3 input your good's name: pear input your good's price: 8 1 ['watermelon', '25'] 2 ['flowers', '30'] 3 ['bottle', '15'] 4 ['flag', '11'] 5 ['pear', '8'] 1.change the item name,2.chage the item price,3.add new item,else:quit: q Process finished with exit code 0
2.商品文本图：
二、
1.正常买东西输出结果：
please input your salary: 2000 1 ['watermelon', '25'] 2 ['flowers', '30'] 3 ['bottle', '15'] 4 ['flag', '11'] 5 ['pear', '8'] please input item number: 1 added ['watermelon', 25] into shopping cart,your current balance is 1975 1 ['watermelon', 25] 2 ['flowers', '30'] 3 ['bottle', '15'] 4 ['flag', '11'] 5 ['pear', '8'] please input item number: 2 added ['flowers', 30] into shopping cart,your current balance is 1945 1 ['watermelon', 25] 2 ['flowers', 30] 3 ['bottle', '15'] 4 ['flag', '11'] 5 ['pear', '8'] please input item number: 3 added ['bottle', 15] into shopping cart,your current balance is 1930 1 ['watermelon', 25] 2 ['flowers', 30] 3 ['bottle', 15] 4 ['flag', '11'] 5 ['pear', '8'] please input item number: q 您已购买的产品有: ['watermelon', 'flowers', 'bottle']
2.买爆输出结果：
please input your salary: 20 1 ['watermelon', '25'] 2 ['flowers', '30'] 3 ['bottle', '15'] 4 ['flag', '11'] 5 ['pear', '8'] please input item number: 1 your current balance is not enough. 1 ['watermelon', 25] 2 ['flowers', '30'] 3 ['bottle', '15'] 4 ['flag', '11'] 5 ['pear', '8'] please input item number:
3.乱输东西的输出结果：
please input your salary: 2000 1 ['watermelon', '25'] 2 ['flowers', '30'] 3 ['bottle', '15'] 4 ['flag', '11'] 5 ['pear', '8'] please input item number: fuck off invalid input 1 ['watermelon', '25'] 2 ['flowers', '30'] 3 ['bottle', '15'] 4 ['flag', '11'] 5 ['pear', '8'] please input item number: