为了以后更好更快速的复习，此博客记录我对作业的总结。对于基础作业，我认为最重要的是过程，至于实现是不是完美，代码是不是完美，虽然重要，但是作业过程中，用到的知识点是值得总结和整理的。
一.购物车：
1. 商品信息- 数量、单价、名称
2. 用户信息- 帐号、密码、余额
3. 用户可充值
4. 购物历史信息
5. 允许用户多次购买，每次可购买多件
6. 余额不足时进行提醒
7. 用户退出时 ，输出当次购物信息
8. 用户下次登陆时可查看购物历史
9. 商品列表分级显示
思路：
1.此作业是day1作业的结合体；
2.用户登录是否首次，分为新用户和旧用户；
3.旧用户查看是否有购物历史；
4.购买时可输入购买数量；
5.余额大于等于购买商品花费则购买成功，购买成功记录购买信息；
6.余额小于购买商品花费则提示充值，要求输入充值金额；
6.购物车自动整理购物商品与花费；
7.可随时查看购物车；
基本流程图：
代码：
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1
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cat
shopping_cart.py
|
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#!/usr/bin/env python
# _*_coding:utf-8_*_
'''
* Created on 2016/10/18 22:01.
* @author: Chinge_Yang.
'''
import
os
import
getpass
import
datetime
menu
=
{
"Mobile phone"
: [
(
"Iphone7"
,
6188
),
(
"Iphone7 plus"
,
7888
),
(
"Xiaomi5"
,
2888
)
],
"Car"
: [
(
"Audi Q5"
,
490000
),
(
"Ferrari 488"
,
4888888
)
],
"Drink"
: [
(
"Milk"
,
59
),
(
"Coffee"
,
30
),
(
"Tea"
,
311
)
]
}
user_file
=
"user.txt"
shopping_log
=
"shopping.log"
money
=
0
#初始金额
all_cost
=
0
shopping_cart
=
{}
exit_user_flag
=
False
exit_flag
=
False
exsit_flag
=
False
if
not
os.path.exists(user_file):
f
=
open
(user_file,
'w'
)
f.close()
if
not
os.path.exists(shopping_log):
f
=
open
(shopping_log,
'w'
)
f.close()
def
show_shopping_cart ():
#显示购物车，更新用户信息，exit前使用
#显示购物车信息
print
(
"You purchased products as below"
.center(
50
,
"*"
))
print
(
"%-20s %-15s %-10s %-20s"
%
(
"Goods"
,
"Price"
,
"Number"
,
"Cost"
))
for
key
in
shopping_cart:
p_name
=
key[
0
]
p_price
=
int
(key[
1
])
p_number
=
int
(shopping_cart[key])
print
(
"%-20s %-15s %-10s \033[32;1m%-20s\033[0m"
%
(p_name,p_price,p_number,p_price
*
p_number))
print
(
"End"
.center(
50
,
"*"
))
print
(
"%-20s %-15s %-10s \033[32;1m%-20s\033[0m"
%
(
"You total cost:"
,"
","
",all_cost))
print
(
"Your balance is [\033[32;1m%s\033[0m]"
%
money)
if
new_user
is
True
:
# 将新用户信息写入到用户文件中
file
=
open
(user_file,
"a"
)
file
.write(
"%s %s %s\n"
%
(user_name, user_passwd, money))
# 用户、密码、金钱存入用户文件
file
.close()
else
:
if
old_money !
=
money:
#充值或买了东西
# 将旧用户信息更新到用户文件中
old_user_info
=
"%s %s %s"
%
(user_name, user_passwd, old_money)
new_user_info
=
"%s %s %s"
%
(user_name, user_passwd, money)
with
open
(user_file) as
file
:
info
=
file
.read()
new_info
=
info.replace(old_user_info,new_user_info)
with
open
(user_file,
"w"
) as
file
:
file
.write(new_info)
while
exit_user_flag
is
not
True
:
#输入用户密码
user_name
=
input
(
"Please input your name:"
).strip()
#user_passwd = input("Please input your password:").strip()
user_passwd
=
getpass.getpass(
"\033[1;33mPlease input your password:\033[0m"
)
if
user_name
=
=
'
' or user_passwd == '
':
continue
elif
' '
in
user_name:
print
(
"\033[31;1mNot allowed to contain spaces!\033[0m"
)
continue
#查看是否存在于用户数据库
user_check
=
open
(user_file)
for
l
in
user_check:
l
=
l.split()
user
=
l[
0
]
passwd
=
l[
1
]
if
user_name
=
=
user:
#老用户
new_user
=
False
#标记为老用户
money
=
int
(l[
2
])
#记录用户余额
old_money
=
money
#旧余额
if
not
passwd
=
=
user_passwd:
print
(
"\033[1;31mYour password is error!\033[0m"
.center(
50
,
"*"
))
else
:
print
(
"\033[1;31mWelcome to go shopping!\033[0m"
.center(
50
,
"-"
))
exit_user_flag
=
True
break
else
:
new_user
=
True
#标记为新用户
exit_user_flag
=
True
user_check.close()
#关闭
if
not
new_user:
#旧用户
#读取购物历史，判断是否有此用户记录
file
=
open
(shopping_log)
for
line
in
file
:
line
=
line.split()
line_user
=
line[
0
]
if
line_user
=
=
user_name:
#存在记录
exsit_flag
=
True
break
#跳出检测
file
.close()
if
exsit_flag
is
True
:
#内容不为空
#只有输入y或者yes才读取显示购物历史，否则不显示
print
(
"Input \033[1;33m[y|yes]\033[0m to view your purchase history,\033[1;33m[others]\033[0m means not."
)
see_history
=
input
(
"Please input:"
).strip()
if
see_history
=
=
"y"
or
see_history
=
=
"yes"
:
# 显示用户购物历史
# output = os.system("grep %s %s" %(user_name,shopping_log))
# print(output.read())
print
(
"User %s shopping history:"
%
user_name)
print
(
"%-20s %-15s %10s %20s"
%
(
"Username"
,
"datetime"
,
"Number"
,
"Goods"
))
file
=
open
(shopping_log)
for
line
in
file
:
line
=
line.split(
"\t"
)
line_user
=
line[
0
]
if
line_user
=
=
user_name:
#存在记录
print
(
"%-10s %-15s %10s %20s"
%
(line[
0
],line[
1
],line[
2
],line[
3
].strip()))
file
.close()
else
:
print
(
"You are not to view your purchase history!"
)
print
(
"-"
.center(
50
,
"-"
))
one_layer_list
=
[]
#一级菜单
while
True
:
while
True
:
#打印各类菜单
print
(
"Species list"
.center(
50
,
"-"
))
for
index, item
in
enumerate
(menu):
print
(
"\033[32;1m%d\033[0m --> %s"
%
(index, item))
one_layer_list.append(item)
print
(
"End"
.center(
50
,
"-"
))
print
(
"[q|b] to quit"
)
once_choice
=
input
(
"Input your choice:"
).strip()
if
once_choice.isdigit():
#输入数字
once_choice
=
int
(once_choice)
if
0
<
=
once_choice <
len
(menu):
#输入正确数字
print
(
"---->Enter \033[32;1m%s\033[0m"
%
(one_layer_list[once_choice]))
two_layer_list
=
menu[one_layer_list[once_choice]]
exit_flag
=
False
#重新进入二级商品菜单
break
#跳出循环，往下走
else
:
print
(
"\033[31;1mNumber out of range, please enter again!\033[0m"
)
else
:
if
once_choice
=
=
"b"
or
once_choice
=
=
"back"
or
once_choice
=
=
"q"
or
once_choice
=
=
"quit"
:
show_shopping_cart()
exit(
"Bye,thanks!"
.center(
50
,
"#"
))
print
(
"\033[31;1mPlease enter the Numbers!\033[0m"
)
while
exit_flag
is
not
True
:
#显示二级商品菜单
print
(
"Product list"
.center(
50
,
'-'
))
for
item
in
enumerate
(two_layer_list):
index
=
item[
0
]
p_name
=
item[
1
][
0
]
p_price
=
item[
1
][
1
]
print
(
"%s.%-20s %-20s"
%
(index,p_name,p_price))
print
(
"End"
.center(
50
,
'-'
))
print
(
"[q|quit] to quit;[b|back] to back"
)
user_choice
=
input
(
"Please choice the product:"
).strip()
if
user_choice.isdigit():
#输入数字
user_choice
=
int
(user_choice)
if
0
<
=
user_choice <
len
(two_layer_list):
product_number
=
input
(
"Please input the number of product:"
).strip()
#输入个数
if
product_number.isdigit():
product_number
=
int
(product_number)
else
:
continue
#重新选择商品和个数
p_item
=
two_layer_list[user_choice]
p_name
=
p_item[
0
]
#商品名
p_price
=
int
(p_item[
1
])
#商品价格
new_added
=
{}
if
p_price
*
product_number <
=
money:
#能付款，表示购买成功
new_added
=
{p_item:product_number}
#整理购物车个数显示总数
for
k, v
in
new_added.items():
if
k
in
shopping_cart.keys():
shopping_cart[k]
+
=
v
else
:
shopping_cart[k]
=
v
money
-
=
p_price
*
product_number
all_cost
+
=
p_price
*
product_number
print
(
"Added [\033[32;1m%d\033[0m] [\033[32;1m%s\033[0m] into shopping cart,"
"your balance is [\033[32;1m%s\033[0m]"
%
(product_number,p_name,money))
with
open
(shopping_log,
"a"
) as
file
:
log
=
"%s\t\"%s\"\t%d\t\"%s\"\n"
%
(user_name,datetime.datetime.now().strftime(
'%Y-%m-%d %H:%M:%S'
),product_number,p_name)
shopping_history
=
file
.write(log)
else
:
#钱不够时，提示充值
print
(
"Your balance is [\033[31;1m%s\033[0m],cannot afford this.."
%
money)
while
True
:
user_charge
=
input
(
"Do you want to charge more money?[\033[32;1my|n|b]\033[0m"
).strip()
if
user_charge
=
=
"y"
or
user_charge
=
=
"yes"
:
charge_number
=
input
(
"Please input your top-up amount:"
).strip()
if
charge_number.isdigit():
charge_number
=
int
(charge_number)
money
+
=
charge_number
#充值成功
print
(
"Your balance is [\033[32;1m%s\033[0m]"
%
money)
else
:
print
(
"Your input is not number!"
)
continue
break
elif
user_charge
=
=
"n"
or
user_charge
=
=
"no"
or
user_charge
=
=
"b"
or
user_charge
=
=
"back"
:
break
#放弃充值
else
:
if
user_choice
=
=
"q"
or
user_choice
=
=
"quit"
:
show_shopping_cart()
exit(
"Bye,thanks!"
.center(
50
,
"#"
))
elif
user_choice
=
=
"c"
or
user_choice
=
=
"check"
:
print
(
"You purchased products as below"
.center(
50
,
"*"
))
print
(
"%-20s %-15s %-10s %-20s"
%
(
"Goods"
,
"Price"
,
"Number"
,
"Cost"
))
for
key
in
shopping_cart:
p_name
=
key[
0
]
p_price
=
int
(key[
1
])
p_number
=
int
(shopping_cart[key])
print
(
"%-20s %-15s %-10s \033[32;1m%-20s\033[0m"
%
(p_name,p_price,p_number,p_price
*
p_number))
print
(
"End"
.center(
50
,
"*"
))
print
(
"%-20s %-15s %-10s \033[32;1m%-20s\033[0m"
%
(
"You total cost:"
,"
","
",all_cost))
print
(
"Your balance is [\033[32;1m%s\033[0m]"
%
money)
elif
user_choice
=
=
"b"
or
user_choice
=
=
"back"
:
exit_flag
=
True
else
:
print
(
"Your input is error!"
)
|
总结：
1.用到的基础知识点不少，不仅复习了day1知识，更灵活运用了列表、字典、元组等；
2.购物车还可以再完美，比如增加商品列表固定排序（如果使用json，我不知道怎么用），增加余额充值接口（使用信用卡）等；
3.对于复杂一些的需求，层次要分明，条理清晰，才能使自己逻辑思维鲜明；
本文转自 ygqygq2 51CTO博客，原文链接：http://blog.51cto.com/ygqygq2/1865581，如需转载请自行联系原作者
