练习—购物车编写

时间：2016-01-14 06:17:39 阅读：322 评论：0 收藏：0 [点我收藏+]

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购物车

一、具体实现功能：

1.用户的注册、登录、充值、余额查询

2.显示商品列表、价格、库存，显示购物车内商品和数量

3.对购物车内商品能进行减少

二、具体流程图

技术分享

三、代码实现

1.用到文件goods.txt

1,apple,1500,100
2,banana,2000,100
3,orange,500,100
4,pear,5000,100

2.为了存取方便、把goods.txt信息序列化写入goods_1.txt，再把一个空字典序列化到user.txt，里面存储着用户名、密码、余额(不过要先注册才有)。

之后用到的文件就是goods_1.txt和user.txt两个了

python2.7

#把物品信息序列化成totallist列表
import pickle
def get_out():
    totallist=[]  #商品信息总列表
    f=file(‘goods.txt‘,‘r‘)
    list=f.readlines()
    for line in list:
        aa=(line).strip().split(‘,‘)
        alist=[aa[0],[aa[1],aa[2],int(aa[3])]]
        totallist.append(alist)
    with open("goods_1.txt","w") as o:
        pickle.dump(totallist,o)    #把新的totallist序列化写入文件

    #先写一个空字典到账户文存储件user.txt
    dic={}
    with open("user.txt","w") as o:
        pickle.dump(dic,o)
get_out()

View Code

python3.4貌似还是用二进制rb，wb来序列和反序列文件比较不会报错

#把物品信息序列化成totallist列表
def get_out():
    totallist=[]  #商品信息总列表
    f=open(‘goods.txt‘,‘rb‘)
    list=f.readlines()
    for line in list:
        aa=(line).strip().split(‘,‘)
        alist=[aa[0],[aa[1],aa[2],int(aa[3])]]
        totallist.append(alist)
    with open("goods_1.txt","wb") as o:
        pickle.dump(totallist,o)    #把新的totallist序列化写入文件

    #先写一个空字典到账户文存储件user.txt
    dic={}
    with open("user.txt","wb") as o:
        pickle.dump(dic,o)
get_out()

View Code

这段代码执行过后就可以抛弃它了（只是为了存取方便）

3、正式代码

python2.7

  1 #!/usr/bin/env python
  2 # -*- coding:utf-8 -*-
  3 import pickle
  4 import time
  5 #注册
  6 def register():
  7     while True:
  8         with open("user.txt","r") as o:
  9             dic=pickle.load(o)
 10             name=raw_input("请输入注册帐号:")
 11             if name in dic.keys():
 12                 print("帐号已存在,请重新输入!")
 13                 continue
 14             else:
 15                 pwd=raw_input("请输入密码:")
 16             dic[name]=[pwd,0,0]
 17             print("注册成功")
 18             with open("user.txt","w") as o:
 19                 pickle.dump(dic,o)
 20             break
 21 #登录
 22 def login_login():#验证用户名密码是否正确
 23      while True:
 24         username=raw_input("请输入账户名:")
 25         with open("user.txt","r") as o:
 26             dic=pickle.load(o)  #取出已经序列化的字典，变成可读的字典
 27         if username in dic.keys():  #如果账户名存在
 28             count=dic[username][2]  #读取字典里的输错次数，count为输错的次数
 29             while True:
 30                 if count<3:
 31                     pwd=raw_input("请输入密码:")
 32                     if dic[username][0] == pwd:
 33                         print ("登录成功!")
 34                         time.sleep(1)
 35                         loginmod(username)
 36                         break
 37                     else:
 38                         count = count+1 #错误一次，count加1
 39                         print ("密码错误")
 40                         continue
 41                 else:
 42                     print ("帐号已被锁定")      #输错3次后锁定账户
 43                     dic[username][2]=3       #把该卡号的错误次数改为3
 44                     with open("user.txt","w") as o:
 45                         pickle.dump(dic,o)       #重新写入文件
 46                         exit()
 47         else:
 48             print ("账号名错误")
 49             continue
 50         break
 51 #购物实现
 52 def shopping(usname):
 53     buy_count=0 #购买物品的总价格
 54     buy_dic={}  #用来放已购买物品的字典
 55     buy_string=""   #用来显示购物车信息的字符串
 56     with open("goods_1.txt","r") as o:
 57         totallist=pickle.load(o)
 58     while True:
 59         print("%s购物车：%s")%("商品列表".ljust(65),buy_string)
 60         print("-----------------------------------")
 61         print("%-16s%-16s%-16s%-16s")%("编号","商品","价格","库存")
 62         for key in totallist:
 63             print("%-14s%-14s%-14s%-14s")%(key[0],key[1][0],key[1][1],key[1][2])#列出列表里的物品
 64         print("0 : 结算  exit : 退出  q : 返回 # : 购物车")
 65         print("-----------------------------------")
 66         name=raw_input("请选择要购买的商品:")
 67         try:
 68             if name in str(range(1,len(totallist)+1)):  #如果选择的数字在range(列表长度)中
 69                 things=totallist[int(name)-1][1][0]      #所选商品
 70                 cost=int(totallist[int(name)-1][1][1])   #所选商品的价格
 71                 if totallist[int(name)-1][1][2]<=0: #判断是否还有库存
 72                     print("库存不足,请重新选择!")
 73                     continue
 74                 print("%s%s")%("你选择了".rjust(20),things.center(6))
 75                 buy_count=buy_count+cost    #选择商品总共的钱
 76                 if things in buy_dic.keys():#如果选择的物品已经在购物车字典里则数量+1
 77                     buy_dic[things]+=1
 78                 else:                       #否则，创建一个新的key，value
 79                     buy_dic[things]=1
 80                 li_1=cut_down(buy_dic)  #把购买物品的字典buy_dic传入cut_down函数，并把返回的值赋给li_1
 81                 buy_string="   ".join(li_1)
 82                 totallist[int(name)-1][1][2] -= 1   #内存中商品对应的存库减1
 83             elif name == "0":
 84                 while True:
 85                     outinput=raw_input("是否结账y/n:")
 86                     if outinput == "y":
 87                         with open("user.txt","r") as o:
 88                             dic=pickle.load(o)  #序列化，变成可读的字典
 89                         money=dic[usname][1]   #该帐号的剩余金钱
 90                         buy_money=buy_count    #购买的商品的总价格
 91                         if money<buy_money:
 92                             update_name=raw_input("帐号余额不足,是否修改购物车商品!y/n")
 93                             if update_name=="y":
 94                                 ccc=add_to(totallist,buy_dic,buy_money)
 95                                 totallist,buy_dic,buy_count=ccc[0],ccc[1],ccc[2]    #把返回的值依次赋值
 96                                 li_2=cut_down(buy_dic)#把购买物品的字典buy_dic传入cut_down函数，并把返回的值赋给li_1
 97                                 buy_string="   ".join(li_2) #把列表变成字符串来显示
 98                                 break
 99                             elif update_name=="n":
100                                 print ("帐号余额不足，请充值!")
101                                 exit()
102                         else:
103                             with open("goods_1.txt","w") as o:#结账后把内存里新的列表写入文件
104                                 pickle.dump(totallist,o)
105                             #-------------------------------
106                             money=money-buy_money   #购买成功后剩余的钱
107                             dic[usname][1]=money    #修改剩余的钱
108                             with open("user.txt","w") as o:#新的dic写入文件
109                                 pickle.dump(dic,o)
110                             print ("结算成功,你购买的物品有:%s")%buy_string
111                             bbb=raw_input("是否要退出程序y/n:")
112                             if bbb == "y":
113                                 exit()
114                             elif bbb=="n":
115                                 buy_dic={}
116                                 buy_string=""
117                                 break
118                             else:
119                                 print ("请输入y/n!")
120                     elif outinput == "n":
121                         break
122                     else:
123                         print ("请输入y/n!")
124             elif name == "exit":
125                 exit()
126             elif name == "#":
127                 ccc=add_to(totallist,buy_dic,buy_count)
128                 totallist,buy_dic,buy_count=ccc[0],ccc[1],ccc[2]
129                 li_2=cut_down(buy_dic)#把购买物品的字典buy_dic传入cut_down函数，并把返回的值赋给li_1
130                 buy_string="   ".join(li_2) #把列表变成字符串来显示
131                 continue
132             elif name == "q":
133                 break
134             else:
135                 print("输入错误!".rjust(25))
136         except Exception:
137                 print ("输入错误!".rjust(25))
138 
139 #把buy_dic里的元素变成列表
140 def cut_down(buy_dic):
141     li_1=[]
142     for k,v in buy_dic.items():
143         str="%s:%s"%(k,v)
144         li_1.append(str)
145     return li_1
146 
147 #把购物车的商品放回商店
148 def add_to(totallist,buy_dic,buy_money):
149     print("购物车")
150     while True:
151         n=1
152         li_1=[]
153         for k,v in buy_dic.items():
154             if v==0:        #判断购物车内商品是否为0，如果是则删除删除商品
155                 buy_dic.pop(k)
156                 continue
157             li=[n,[k,v]]
158             li_1.append(li)
159             n = n+1
160         print("%-12s%-12s%-12s")%("编号","商品","数量")
161         for key in li_1:
162             print("%-10s%-10s%-10s")%(key[0],key[1][0],key[1][1])#列出列表里的物品
163         print("q 返回")
164         aa=raw_input("请选择要退货的商品!")
165         if aa in str(range(1,len(li_1)+1)):
166             things=li_1[int(aa)-1][1][0]      #所选商品
167             if buy_dic[things]>0:       #如果购物车内的商品数量大于0
168                 buy_dic[things]-=1       #数量-1
169                 for thin in totallist:      #循环totallist
170                     if thin[1][0]==things:      #如果找到循环totallist内和该物品一样时
171                         id=thin[0]       #找出该物品在totallist内的id
172                         totallist[int(id)-1][1][2] += 1     #totallist内该物品数量回+1
173                         price=totallist[int(id)-1][1][1]
174                         buy_money=buy_money-int(price)
175                 continue
176             else:
177                 print("购物车已没有该物品!")
178         elif aa=="q":
179             break
180         else:
181             print("输入错误!")
182     return totallist,buy_dic,buy_money
183 #充值
184 def pay(usname):
185      while True:
186         input_cash=raw_input("请输入充值金额:")
187         if input_cash.isdigit():
188             with open("user.txt","r") as o:
189                 dic=pickle.load(o)
190             money=dic[usname][1]
191             left_money=int(money)+int(input_cash)
192             print ("充值%s,余额%s"%(input_cash,left_money))
193             dic[usname][1]=left_money   #把剩余的钱写入字典
194             with open("user.txt","w") as o:
195                 pickle.dump(dic,o)  #重新写入文件
196                 break
197         else:
198             print ("请输入数字!")
199 
200 #查询余额
201 def demand(usname):
202     with open("user.txt","r") as o:
203         dic=pickle.load(o)
204         money=dic[usname][1]
205         print ("你的可用余额还有:%s")%money
206 
207 #登录成功后显示
208 def loginmod(usname):
209     while True:
210         print ‘1、查询 2、购物 3、充值 q、返回 exit、退出‘
211         inp = raw_input("请选择：")
212         if inp == "1":
213             demand(usname)
214         elif inp == "2":
215             shopping(usname)
216         elif inp == "3":
217             pay(usname)
218         elif inp == "q":
219            return
220         elif inp == "exit":
221            exit()
222 
223 #主程序
224 if __name__ == "__main__":
225     while True:
226         print("1、注册 2、登录 exit、退出")
227         aa=raw_input("请选择：")
228         if aa == "1":
229             register()
230         elif aa == "2":
231             login_login()
232         elif aa == "exit":
233             exit()
234         else:
235             print("输入错误!")

python2.7购物车

python3.4

  1 #!/usr/bin/env python
  2 # -*- coding:utf-8 -*-
  3 import pickle
  4 import time
  5 import getpass
  6 #注册
  7 def register():
  8     while True:
  9         with open("user.txt","rb") as o:
 10             dic=pickle.load(o)
 11             name=input("请输入注册帐号:")
 12             if name in dic.keys():
 13                 print("帐号已存在,请重新输入!")
 14                 continue
 15             else:
 16                 pwd=input("请输入密码:")
 17             dic[name]=[pwd,0,0]
 18             print("注册成功")
 19             with open("user.txt","wb") as o:
 20                 pickle.dump(dic,o)
 21             break
 22 #登录
 23 def login_login():#验证用户名密码是否正确
 24      while True:
 25         username=input("请输入账户名:")
 26         with open("user.txt","rb") as o:
 27             dic=pickle.load(o)  #取出已经序列化的字典，变成可读的字典
 28         if username in dic.keys():  #如果账户名存在
 29             count=dic[username][2]  #读取字典里的输错次数，count为输错的次数
 30             while True:
 31                 if count<3:
 32                     pwd=input("请输入密码:")
 33                     if dic[username][0] == pwd:
 34                         print ("登录成功!")
 35                         time.sleep(1)
 36                         loginmod(username)
 37                         break
 38                     else:
 39                         count = count+1 #错误一次，count加1
 40                         print ("密码错误")
 41                         continue
 42                 else:
 43                     print ("帐号已被锁定")      #输错3次后锁定账户
 44                     dic[username][2]=3       #把该卡号的错误次数改为3
 45                     with open("user.txt","w") as o:
 46                         pickle.dump(dic,o)       #重新写入文件
 47                         exit()
 48         else:
 49             print ("账号名错误")
 50             continue
 51         break
 52 #购物实现
 53 def shopping(usname):
 54     buy_count=0 #购买物品的总价格
 55     buy_dic={}  #用来放已购买物品的字典
 56     buy_string=""   #用来显示购物车信息的字符串
 57     with open("goods_1.txt","rb") as o:
 58         totallist=pickle.load(o)
 59     while True:
 60         number=[]
 61         print("%s购物车：%s"%("商品列表".ljust(65),buy_string))
 62         print("-----------------------------------")
 63         print("%-16s%-16s%-16s%-16s"%("编号","商品","价格","库存"))
 64         for key in totallist:
 65             print("%-14s%-14s%-14s%-14s"%(key[0],key[1][0],key[1][1],key[1][2]))#列出列表里的物品
 66             number.append(key[0])
 67         print("0 : 结算  exit : 退出  q : 返回 # : 购物车")
 68         print("-----------------------------------")
 69         name=input("请选择要购买的商品:")
 70         try:
 71             if name in number:  #如果选择的数字在range(列表长度)中
 72                 things=totallist[int(name)-1][1][0]      #所选商品
 73                 cost=int(totallist[int(name)-1][1][1])   #所选商品的价格
 74                 if totallist[int(name)-1][1][2]<=0: #判断是否还有库存
 75                     print("库存不足,请重新选择!")
 76                     continue
 77                 print("%s%s"%("你选择了".rjust(20),things.center(6)))
 78                 buy_count=buy_count+cost    #选择商品总共的钱
 79                 if things in buy_dic.keys():#如果选择的物品已经在购物车字典里则数量+1
 80                     buy_dic[things]+=1
 81                 else:                       #否则，创建一个新的key，value
 82                     buy_dic[things]=1
 83                 li_1=cut_down(buy_dic)  #把购买物品的字典buy_dic传入cut_down函数，并把返回的值赋给li_1
 84                 buy_string="   ".join(li_1)
 85                 totallist[int(name)-1][1][2] -= 1   #内存中商品对应的存库减1
 86             elif name == "0":
 87                 while True:
 88                     outinput=input("是否结账y/n:")
 89                     if outinput == "y":
 90                         with open("user.txt","rb") as o:
 91                             dic=pickle.load(o)  #序列化，变成可读的字典
 92                         money=dic[usname][1]   #该帐号的剩余金钱
 93                         buy_money=buy_count    #购买的商品的总价格
 94                         if money<buy_money:
 95                             update_name=input("帐号余额不足,是否修改购物车商品!y/n")
 96                             if update_name=="y":
 97                                 ccc=add_to(totallist,buy_dic,buy_money)
 98                                 print(ccc)
 99                                 totallist,buy_dic,buy_count=ccc[0],ccc[1],ccc[2]    #把返回的值依次赋值
100                                 li_2=cut_down(buy_dic)#把购买物品的字典buy_dic传入cut_down函数，并把返回的值赋给li_1
101                                 buy_string="   ".join(li_2) #把列表变成字符串来显示
102                                 break
103                             elif update_name=="n":
104                                 print ("帐号余额不足，请充值!")
105                                 exit()
106                         else:
107                             with open("goods_1.txt","wb") as o:#结账后把内存里新的列表写入文件
108                                 pickle.dump(totallist,o)
109                             #-------------------------------
110                             money=money-buy_money   #购买成功后剩余的钱
111                             dic[usname][1]=money    #修改剩余的钱
112                             with open("user.txt","wb") as o:#新的dic写入文件
113                                 pickle.dump(dic,o)
114                             print ("结算成功,你购买的物品有:%s"%buy_string)
115                             bbb=input("是否要退出程序y/n:")
116                             if bbb == "y":
117                                 exit()
118                             elif bbb=="n":
119                                 buy_dic={}
120                                 buy_string=""
121                                 break
122                             else:
123                                 print ("请输入y/n!")
124                     elif outinput == "n":
125                         break
126                     else:
127                         print ("请输入y/n!")
128             elif name == "exit":
129                 exit()
130             elif name == "#":
131                 ccc=add_to(totallist,buy_dic,buy_count)
132                 totallist,buy_dic,buy_count=ccc[0],ccc[1],ccc[2]
133                 li_2=cut_down(buy_dic)#把购买物品的字典buy_dic传入cut_down函数，并把返回的值赋给li_1
134                 buy_string="   ".join(li_2) #把列表变成字符串来显示
135                 continue
136             elif name == "q":
137                 break
138             else:
139                 print("输入错误!".rjust(25))
140         except Exception:
141                 print ("输入错误!".rjust(25))
142 
143 #把buy_dic里的元素变成列表
144 def cut_down(buy_dic):
145     li_1=[]
146     for k,v in buy_dic.items():
147         str="%s:%s"%(k,v)
148         li_1.append(str)
149     return li_1
150 
151 #把购物车的商品放回商店
152 def add_to(totallist,buy_dic,buy_money):
153     print("购物车")
154     while True:
155         n=1
156         li_1=[]
157         number=[]
158         for k,v in buy_dic.items():
159             li=[n,[k,v]]
160             li_1.append(li)
161             n = n+1
162         print("%-12s%-12s%-12s"%("编号","商品","数量"))
163         for key in li_1:
164             print("%-10s%-10s%-10s"%(key[0],key[1][0],key[1][1]))#列出列表里的物品
165             number.append(str(key[0]))
166         print("q 返回")
167         aa=input("请选择要退货的商品!")
168         if aa in number:
169             things=li_1[int(aa)-1][1][0]      #所选商品
170             if int(buy_dic[things])>0:       #如果购物车内的商品数量大于0
171                 buy_dic[things]-=1       #数量-1
172                 if buy_dic[things]==0:  #如果数量为0，删除该物品
173                     buy_dic.pop(things)
174                 for thin in totallist:      #循环totallist
175                     if thin[1][0]==things:      #如果找到循环totallist内和该物品一样时
176                         id=thin[0]       #找出该物品在totallist内的id
177                         totallist[int(id)-1][1][2] += 1     #totallist内该物品数量回+1
178                         price=totallist[int(id)-1][1][1]
179                         buy_money=buy_money-int(price)
180                 continue
181             else:
182                 print("购物车已没有该物品!")
183         elif aa == "q":
184             break
185         else:
186             print("输入错误!")
187     return totallist,buy_dic,buy_money
188 #充值
189 def pay(usname):
190      while True:
191         input_cash=input("请输入充值金额:")
192         if input_cash.isdigit():
193             with open("user.txt","rb") as o:
194                 dic=pickle.load(o)
195             money=dic[usname][1]    #账户余额
196             left_money=int(money)+int(input_cash)   #账户余额加充值的钱
197             print ("充值%s,余额%s"%(input_cash,left_money))
198             dic[usname][1]=left_money   #把剩余的钱写入字典
199             with open("user.txt","wb") as o:
200                 pickle.dump(dic,o)      #写入新字典
201                 break
202         else:
203             print ("请输入数字!")
204 
205 #查询余额
206 def demand(usname):
207     with open("user.txt","rb") as o:
208         dic=pickle.load(o)
209         money=dic[usname][1]
210         print ("你的可用余额还有:%r"%(money))
211 
212 #登录成功后显示
213 def loginmod(usname):
214     while True:
215         print (‘1、查询 2、购物 3、充值 q、返回 exit、退出‘)
216         inp = input("请选择：")
217         if inp == "1":
218             demand(usname)
219         elif inp == "2":
220             shopping(usname)
221         elif inp == "3":
222             pay(usname)
223         elif inp == "q":
224            return
225         elif inp == "exit":
226            exit()
227 
228 #主程序
229 if __name__ == "__main__":
230     while True:
231         print("1、注册 2、登录 exit、退出")
232         aa=input("请选择：")
233         if aa == "1":
234             register()
235         elif aa == "2":
236             login_login()
237         elif aa == "exit":
238             exit()
239         else:
240             print("输入错误!")