函数&模块&文件操作相关

一、函数

1.函数定义

函数，一个用于专门实现某个功能的代码块（可重用）。

【1】内置函数

len、bin、oct、hex 等

【2】自定义函数

def send_email():
    # 写了10行代码，实现了发送邮件。
    pass

send_email()

# 定义了一个函数，功能代码块
def send_email():
    # 写了10行代码，实现了发送邮件。
    pass

goods = [
    {
    
    "name": "电脑", "price": 1999},
    {
    
    "name": "鼠标", "price": 10},
    {
    
    "name": "游艇", "price": 20},
    {
    
    "name": "美女", "price": 998}
]
for index in range(len(goods)):
    item = goods[index]
    print(index + 1, item['name'], item['price'])

# 调用并执行函数
send_email()

while True:
    num = input("请输入要选择的商品序号(Q/q)：")  # "1"
    if num.upper() == "Q":
        break
    if not num.isdecimal():
        print("用输入的格式错误")
        break
    num = int(num)
    send_email()
    if num > 4 or num < 0:
        print("范围选择错误")
        break
    target_index = num - 1
    choice_item = goods[target_index]
    print(choice_item["name"], choice_item['price'])
    send_email()

二、模块

1.模块定义

集成了很多功能的函数集合。

【1】内置模块，Python内部帮助我们提供好的。

import random

num = random.randint(0,19)

import decimal

v1 = decimal.Decimal("0.1")
v2 = decimal.Decimal("0.2")
v3 = v1 + v2
print(v3) # 0.3

【2】第三方模块，网上下载别人写好的模块（功能集合）。

【3】自定义模块

三、文件操作相关

每种格式包含很多相关操作，大家在学习的过程中只要掌握知识点的用法，参考笔记可以实现相关的练习即可，不必背会（在企业开发过程中也是边搜边实现。

1.文件操作

【1】读文件

读文本文件

# 1.打开文件
#	- 路径：
#		相对路径：'info.txt'
#		绝对路径：'/Users/wupeiqi/PycharmProjects/luffyCourse/day09/info.txt'
# 	- 模式
# 		rb，表示读取文件原始的二进制（r, 读 read；b, 二进制 binary；）
# 1.打开文件
file_object = open('info.txt', mode='rb')
# 2.读取文件内容，并赋值给data
data = file_object.read()
# 3.关闭文件
file_object.close()

print(data) # b'alex-123\n\xe6\xad\xa6\xe6\xb2\x9b\xe9\xbd\x90-123'  读取的是文件的二进制
text = data.decode("utf-8")    #将文本的内容从字节转换成字符串
print(text)

# 1.打开文件
file_object = open('info.txt', mode='rt', encoding='utf-8')    # 直接读取到文件的字符串类型，无需像上方一样手动转换

# 2.读取文件内容，并赋值给data
data = file_object.read()

# 3.关闭文件
file_object.close()

print(data)

读图片等非文本内容文件。

file_object = open('a1.png', mode='rb')
data = file_object.read()
file_object.close()

print(data) # \x91\xf6\xf2\x83\x8aQFfv\x8b7\xcc\xed\xc3}\x7fT\x9d{.3.\xf1{\xe8\...

== 注意事项==

路径
- 相对路径，当前程序的目录下找文件
- 绝对路径

# 1.打开文件
file_object = open('/Users/wupeiqi/PycharmProjects/luffyCourse/day09/info.txt', mode='rt', encoding='utf-8')
# 2.读取文件内容，并赋值给data
data = file_object.read()
# 3.关闭文件
file_object.close()

windows系统中写绝对路径容易出问题：

# file_object = open('C:\\new\\info.txt', mode='rt', encoding='utf-8')   

file_object = open(r'C:\new\info.txt', mode='rt', encoding='utf-8')    # 直接写win绝对路径会报错，可以在路径前方加上r，或者使用双斜杠 
data = file_object.read()
file_object.close()
print(data)

读文件时，文件不存在程序会报错。

Traceback (most recent call last):
  File "/Users/wupeiqi/PycharmProjects/luffyCourse/day09/2.读文件.py", line 2, in <module>
    file_object = open('infower.txt', mode='rt', encoding='utf-8')
FileNotFoundError: [Errno 2] No such file or directory: 'infower.txt'

# 判断路径是否存在：
import os

file_path = "/Users/wupeiqi/PycharmProjects/luffyCourse/day09/info.txt"
exists = os.path.exists(file_path)    #判断路径是否存在，返回一个bool 
if exists:
    # 1.打开文件
    file_object = open('infower.txt', mode='rt', encoding='utf-8')
    # 2.读取文件内容，并赋值给data
    data = file_object.read()
    # 3.关闭文件
    file_object.close()
    print(data)
else:
    print("文件不存在")

【2】写文件

写文本文件

# 1.打开文件
# 路径：t1.txt
# 模式：wb（要求写入的内容需要是字节类型）
file_object = open("t1.txt", mode='wb')

# 2.写入内容
file_object.write(    "张三".encode("utf-8")    )

# 3.文件关闭
file_object.close()

file_object = open("t1.txt", mode='wt', encoding='utf-8')   #通过wt写入内容更方便，不用进行转换

file_object.write("张三")

file_object.close()

写图片等文件

#相当于复制图片
f1 = open('a1.png',mode='rb')
content = f1.read()
f1.close()

f2 = open('a2.png',mode='wb')
f2.write(content)
f2.close()

基础案例：

# 【1】案例1：用户注册

user = input("请输入用户名：")
pwd = input("请输入密码：")
data = "{}-{}".format(user, pwd)
file_object = open("files/info.txt", mode='wt', encoding='utf-8')   #打开某一文件时，若是文件不存在，则会创建一个
file_object.write(data)
file_object.close()


#【2】 案例2：多用户注册

# 通过w写入文件，先清空文件；再在文件中写入内容。解决方案：不要反复打开文件即可
file_object = open("files/info.txt", mode='wt', encoding='utf-8')  
while True:
    user = input("请输入用户名：")
    if user.upper() == "Q":
        break
    pwd = input("请输入密码：")
    data = "{}-{}\n".format(user, pwd)     #  \n 在程序中是换行的意思，加入后可让输如内容自动换行

    file_object.write(data)
file_object.close()

小高级案例：（超前）

# 利用Python想某个网址发送请求并获取结果（利用第三方的模块）
# 下载第三方模块requests
pip install requests   # 若使用该方法安装报错，则使用下边的代码进行安装

或者：  /Library/Frameworks/Python.framework/Versions/3.9/bin/pip3 install requests  # 此代码中的路径为py的安装目录
# 使用第三方模块
import requests

res = requests.get(url="网址")
print(res)

# 【1】 案例1：去网上下载一点文本，文本信息写入文件。
import requests

res = requests.get(
    url="https://movie.douban.com/j/search_subjects?type=movie&tag=%E7%83%AD%E9%97%A8&sort=recommend&page_limit=20&page_start=20",
    headers={
    
    
        "User-Agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36"
    }
)

#  res.content   网络传输的原始二进制信息（bytes）


file_object = open('files/log1.txt', mode='wb')
file_object.write(res.content)
file_object.close()



# 【2】案例2：去网上下载一张图片，图片写入本地文件。
import requests

res = requests.get(
    url="https://hbimg.huabanimg.com/c7e1461e4b15735fbe625c4dc85bd19904d96daf6de9fb-tosv1r_fw1200",
    headers={
    
    
        "User-Agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36"
    }
)

# 网络传输的原始二进制信息（bytes）
# res.content

file_object = open('files/张三.png', mode='wb')
file_object.write(res.content)
file_object.close()

注意事项

路径
绝对路径
相对路径
文件不存在时，w模式会新建然后再写入内容；文件存在时，w模式会清空文件再写入内容。

【3】文件的打开模式

========= ===============================================================
Character Meaning
--------- ---------------------------------------------------------------
'r'       open for reading (default)
'w'       open for writing, truncating the file first
'x'       create a new file and open it for writing
'a'       open for writing, appending to the end of the file if it exists

'b'       binary mode
't'       text mode (default)

'+'       open a disk file for updating (reading and writing)

The default mode is 'rt' (open for reading text).

关于文件的打开模式常见应用有：

只读：r、rt、rb （用）
存在，读
不存在，报错
只写：w、wt、wb（用）

存在，清空再写
不存在，创建再写
只写：x、xt、xb（了解即可）

存在，报错
不存在，创建再写。
只写：a、at、ab【尾部追加】（用）

存在，尾部追加。
不存在，创建再写。
读写

r+、rt+、rb+，默认光标位置：起始位置

file_object = open('info.txt', mode='rt+')

# 读取内容
data = file_object.read()
print(data)

# 写入内容
file_object.write("你好呀")

file_object.close()

file_object = open('info.txt', mode='rt+')

# 写入内容
file_object.write("zhan")

# 读取内容
data = file_object.read()
print(data)  # -123  此处从光标位置开始读取，故没有读取全部内容

file_object.close()

w+、wt+、wb+，默认光标位置：起始位置（清空文件）

file_object = open('info.txt', mode='wt+')

# 读取内容
data = file_object.read()   
print(data)

# 写入内容
file_object.write("你好呀")

# 将光标位置重置起始
file_object.seek(0)

# 读取内容
data = file_object.read()
print(data)

file_object.close()

x+、xt+、xb+，默认光标位置：起始位置（新文件）

a+、at+、ab+，默认光标位置：末尾

file_object = open('info.txt', mode='at+')

# 写入内容
file_object.write("张三")

# 将光标位置重置起始
file_object.seek(0)

# 读取内容
data = file_object.read()
print(data)

file_object.close()

【多用户注册案例】

while True:
    user = input("用户名：")
    if user.upper() == "Q":
        break
    pwd = input("密码：")

    data = "{}-{}\n".format(user, pwd)

    file_object = open('files/account.txt', mode='a')
    file_object.write(data)
    file_object.close()

file_object = open('files/account.txt', mode='a')

while True:
    user = input("用户名：")
    if user.upper() == "Q":
        break
    pwd = input("密码：")
    data = "{}-{}\n".format(user, pwd)
    file_object.write(data)

file_object.close()

【4】常见功能

在上述对文件的操作中，我们只使用了write和read来对文件进行读写，其实在文件操作中还有很多其他的功能来辅助实现更好的读写文件的内容。

read，读

读所有【常用】

f = open('info.txt', mode='r',encoding='utf-8')
data = f.read()
f.close()

f = open('info.txt', mode='rb')
data = f.read()
f.close()

读n个字符（字节）【会用到】

f = open('info.txt', mode='r', encoding='utf-8')
# 读1个字符
data = f.read(1)
f.close()

print(data) # 武

f = open('info.txt', mode='r',encoding='utf-8')

# 读1个字符
chunk1 = f.read(1)
chunk2 = f.read(2)
print(chunk1,chunk2)

f.close()

f = open('info.txt', mode='rb')

# 读1个字节
data = f.read(3)
f.close()

print(data, type(data))  # b'\xe6\xad\xa6' <class 'bytes'>

f = open('info.txt', mode='rb')

# 读1个字节
chunk1 = f.read(3)
chunk2 = f.read(3)
chunk3 = f.read(1)
print(chunk1,chunk2,chunk3)

f.close()

readline，读一行

f = open('info.txt', mode='r', encoding='utf-8')

v1 = f.readline()
print(v1)

v2 = f.readline()
print(v2)

f.close()

f = open('info.txt', mode='r', encoding='utf-8')
v1 = f.readline()
print(v1)
f.close()

f = open('info.txt', mode='r', encoding='utf-8')
v2 = f.readline()
print(v2)
f.close()

readlines，读所有行，每行作为列表的一个元素

f = open('info.txt', mode='rb')

data_list = f.readlines()

f.close()

print(data_list)

循环，读大文件（readline加强版）【常见】

# 大文件读取，且读完后会自动终止，可搭配for循环
f = open('info.txt', mode='r', encoding='utf-8')
for line in f:
    print(line.strip())
f.close()

write，写

f = open('info.txt', mode='a',encoding='utf-8')
f.write("武沛齐")
f.close()

f = open('info.txt', mode='ab')
f.write( "武沛齐".encode("utf-8") )
f.close()

flush，刷到硬盘

f = open('info.txt', mode='a',encoding='utf-8')

while True:
    # 由于写入不是写到了硬盘，而是写在缓冲区，系统会将缓冲区的内容刷到硬盘，但时间不定，使用flush可将写入缓冲区的内容立即刷到硬盘中。
	f.write("武沛齐")
    f.flush()

f.close()

file_object = open('files/account.txt', mode='a')

while True:
    user = input("用户名：")
    if user.upper() == "Q":
        break
    pwd = input("密码：")
    data = "{}-{}\n".format(user, pwd)
    file_object.write(data)
    file_object.flush()

file_object.close()

移动光标位置（字节）

f = open('info.txt', mode='r+', encoding='utf-8')

# 移动到指定字节的位置
f.seek(3)
f.write("武沛齐")

f.close()

注意：在a模式下，调用write在文件中写入内容时，永远只能将内容写入到尾部，不会写到光标的位置。

获取当前光标位置

f = open('info.txt', mode='r', encoding='utf-8')

p1 = f.tell()
print(p1)  # 0

f.read(3)  # 读3个字符 3*3=9字节

p2 = f.tell()
print(p2)  # 9

f.close()

f = open('info.txt', mode='rb')

p1 = f.tell()
print(p1)  # 0

f.read(3)  # 读3个字节

p2 = f.tell()
print(p2)  # 3

f.close()

【5】上下文管理

之前对文件进行操作时，每次都要打开和关闭文件，比较繁琐且容易忘记关闭文件。

以后再进行文件操作时，推荐大家使用with上下文管理，它可以自动实现关闭文件。

with open("xxxx.txt", mode='rb') as file_object:
    data = file_object.read()
    print(data)

在Python 2.7 后，with又支持同时对多个文件的上下文进行管理，即：

with open("xxxx.txt", mode='rb') as f1, open("xxxx.txt", mode='rb') as f2:
    pass

【6】练习题

补充代码：实现下载视频并保存到本地

   import requests
   
   res = requests.get(
       url="https://f.video.weibocdn.com/000pTZJLgx07IQgaH7HW010412066BJV0E030.mp4?label=mp4_720p&template=1280x720.25.0&trans_finger=1f0da16358befad33323e3a1b7f95fc9&media_id=4583105541898354&tp=8x8A3El:YTkl0eM8&us=0&ori=1&bf=2&ot=h&ps=3lckmu&uid=3ZoTIp&ab=3915-g1,966-g1,3370-g1,3601-g0,3601-g0,3601-g0,1493-g0,1192-g0,1191-g0,1258-g0&Expires=1608204895&ssig=NdYpDIEXSS&KID=unistore,video",
       headers={
    
    
           "User-Agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36"
       }
   )
   
   # 视频的文件内容
   res.content

完整代码：

import requests

res = requests.get(
    url="https://f.video.weibocdn.com/000pTZJLgx07IQgaH7HW010412066BJV0E030.mp4?label=mp4_720p&template=1280x720.25.0&trans_finger=1f0da16358befad33323e3a1b7f95fc9&media_id=4583105541898354&tp=8x8A3El:YTkl0eM8&us=0&ori=1&bf=2&ot=h&ps=3lckmu&uid=3ZoTIp&ab=3915-g1,966-g1,3370-g1,3601-g0,3601-g0,3601-g0,1493-g0,1192-g0,1191-g0,1258-g0&Expires=1608204895&ssig=NdYpDIEXSS&KID=unistore,video",
    headers={
    
    
        "User-Agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36"
    }
)

# 视频的文件内容
with open('nba.mp4' ,mode='wb') as file_object:
    file_object.read(res.content)
res.content

日志分析，计算某用户223.73.89.192访问次数。日志文件如下：access.log

   49.89.167.91 - - [17/Dec/2020:03:43:50 +0800] "GET /wiki/detail/3/40 HTTP/1.1" 301 0 "-" "Mozilla/5.0(Linux;Android 5.1.1;OPPO A33 Build/LMY47V;wv) AppleWebKit/537.36(KHTML,link Gecko) Version/4.0 Chrome/43.0.2357.121 Mobile Safari/537.36 LieBaoFast/4.51.3" "-"
   49.89.167.91 - - [17/Dec/2020:03:44:11 +0800] "GET /wiki/detail/3/40/ HTTP/1.1" 200 8033 "-" "Mozilla/5.0(Linux;Android 5.1.1;OPPO A33 Build/LMY47V;wv) AppleWebKit/537.36(KHTML,link Gecko) Version/4.0 Chrome/43.0.2357.121 Mobile Safari/537.36 LieBaoFast/4.51.3" "-"
   203.208.60.66 - - [17/Dec/2020:03:47:58 +0800] "GET /media/uploads/2019/11/17/pic/s1.png HTTP/1.1" 200 710728 "-" "Googlebot-Image/1.0" "-"
   223.73.89.192 - - [17/Dec/2020:03:48:26 +0800] "GET /wiki/detail/3/40/ HTTP/1.1" 200 8033 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36 Edg/87.0.664.60" "-"
   223.73.89.192 - - [17/Dec/2020:03:48:26 +0800] "GET /static/stark/plugins/font-awesome/css/font-awesome.css HTTP/1.1" 200 37414 "https://pythonav.com/wiki/detail/3/40/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36 Edg/87.0.664.60" "-"
   223.73.89.192 - - [17/Dec/2020:03:48:26 +0800] "GET /static/stark/plugins/bootstrap/css/bootstrap.css HTTP/1.1" 200 146010 "https://pythonav.com/wiki/detail/3/40/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36 Edg/87.0.664.60" "-"
   223.73.89.192 - - [17/Dec/2020:03:48:26 +0800] "GET /static/web/css/commons.css HTTP/1.1" 200 3674 "https://pythonav.com/wiki/detail/3/40/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36 Edg/87.0.664.60" "-"
   223.73.89.192 - - [17/Dec/2020:03:48:26 +0800] "GET /static/mdeditor/editormd/css/editormd.preview.css HTTP/1.1" 200 60230 "https://pythonav.com/wiki/detail/3/40/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36 Edg/87.0.664.60" "-"
   223.73.89.192 - - [17/Dec/2020:03:48:26 +0800] "GET /static/stark/js/jquery-3.3.1.min.js HTTP/1.1" 200 86927 "https://pythonav.com/wiki/detail/3/40/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36 Edg/87.0.664.60" "-"
   223.73.89.192 - - [17/Dec/2020:03:48:26 +0800] "GET /static/stark/plugins/bootstrap/js/bootstrap.min.js HTTP/1.1" 200 37045 "https://pythonav.com/wiki/detail/3/40/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36 Edg/87.0.664.60" "-"
   223.73.89.192 - - [17/Dec/2020:03:48:26 +0800] "GET /static/mdeditor/editormd/lib/marked.min.js HTTP/1.1" 200 19608 "https://pythonav.com/wiki/detail/3/40/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36 Edg/87.0.664.60" "-"
   223.73.89.192 - - [17/Dec/2020:03:48:27 +0800] "GET /static/mdeditor/editormd/lib/prettify.min.js HTTP/1.1" 200 17973 "https://pythonav.com/wiki/detail/3/40/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36 Edg/87.0.664.60" "-"
   223.73.89.192 - - [17/Dec/2020:03:48:27 +0800] "GET /static/mdeditor/editormd/fonts/fontawesome-webfont.woff2?v=4.3.0 HTTP/1.1" 200 56780 "https://pythonav.com/static/mdeditor/editormd/css/editormd.preview.css" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36 Edg/87.0.664.60" "-"
   223.73.89.192 - - [17/Dec/2020:03:48:27 +0800] "GET /static/mdeditor/editormd/editormd.js HTTP/1.1" 200 163262 "https://pythonav.com/wiki/detail/3/40/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36 Edg/87.0.664.60" "-"
   223.73.89.192 - - [17/Dec/2020:03:48:28 +0800] "GET /static/mdeditor/mdeditor-preview-init.js HTTP/1.1" 200 261 "https://pythonav.com/wiki/detail/3/40/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36 Edg/87.0.664.60" "-"
   223.73.89.192 - - [17/Dec/2020:03:48:29 +0800] "GET /static/stark/plugins/font-awesome/fonts/fontawesome-webfont.woff2?v=4.7.0 HTTP/1.1" 200 77160 "https://pythonav.com/static/stark/plugins/font-awesome/css/font-awesome.css" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36 Edg/87.0.664.60" "-"
   223.73.89.192 - - [17/Dec/2020:03:48:29 +0800] "GET /media/uploads/2019/02/22/Gobook/_book/ssl2.png HTTP/1.1" 200 203535 "https://pythonav.com/wiki/detail/3/40/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36 Edg/87.0.664.60" "-"

查询方法
分析：

total_count = 0
ip = "223.73.89.192"
with open('files/access.log', mode='r', encoding='utf-8') as file_object:
    for line in file_object:
        if not line.startswith(ip):
            continue
        total_count += 1
print(total_count)

日志分析升级，计算所有用户的访问次数。

user_dict = {
    
    }
with open('files/access.log',mode='r',encoding='utf-8') as file_object:
    for line in file_object:
        user_ip = line.split(" ")[0]
        if user_ip in user_dict:
            # user_dict[user_ip] = user_dict[user_ip] + 1
            user_dict[user_ip] += 1
        else:
            user_dict[user_ip] = 1
print(user_dict)

筛选出股票当前价大于 20 的所有股票数据。

   股票代码,股票名称,当前价,涨跌额,涨跌幅,年初至今,成交量,成交额,换手率,市盈率(TTM),股息率,市值
   SH601778,N晶科,6.29,+1.92,+43.94%,+43.94%,259.66万,1625.52万,0.44%,22.32,-,173.95亿
   SH688566,吉贝尔,52.66,+6.96,+15.23%,+122.29%,1626.58万,8.09亿,42.29%,89.34,-,98.44亿
   SH688268,华特气体,88.80,+11.72,+15.20%,+102.51%,622.60万,5.13亿,22.87%,150.47,-,106.56亿
   SH600734,实达集团,2.60,+0.24,+10.17%,-61.71%,1340.27万,3391.14万,2.58%,亏损,0.00%,16.18亿
   SH900957,凌云B股,0.36,+0.033,+10.09%,-35.25%,119.15万,42.10万,0.65%,44.65,0.00%,1.26亿
   SZ000584,哈工智能,6.01,+0.55,+10.07%,-4.15%,2610.86万,1.53亿,4.36%,199.33,0.26%,36.86亿
   SH600599,熊猫金控,6.78,+0.62,+10.06%,-35.55%,599.64万,3900.23万,3.61%,亏损,0.00%,11.25亿
   SH600520,文一科技,8.21,+0.75,+10.05%,-24.05%,552.34万,4464.69万,3.49%,亏损,0.00%,13.01亿
   SH603682,锦和商业,11.73,+1.07,+10.04%,+48.29%,2746.63万,3.15亿,29.06%,29.62,-,55.42亿
   SZ300831,派瑞股份,12.27,+1.12,+10.04%,+208.29%,25.38万,311.41万,0.32%,60.59,-,39.26亿

with open('files/stock.txt', mode='r', encoding='utf-8') as file_object:
    # 1.跳过第一行
    file_object.readline()
    # 2.接着往下读
    for line in file_object:
        text = line.split(',')[2]
        price = float(text)
        if price > 20:
            print(line.strip())

根据要求修改文件的内容，原文件内容如下：ha.conf

   global       
           log 127.0.0.1 local2
           daemon
           maxconn 256
           log 127.0.0.1 local2 info
   defaults
           log global
           mode http
           timeout connect 5000ms
           timeout client 50000ms
           timeout server 50000ms
           option  dontlognull
   
   listen stats :8888
           stats enable
           stats uri       /admin
           stats auth      admin:1234
   
   frontend oldboy.org
           bind 0.0.0.0:80
           option httplog
           option httpclose
           option  forwardfor
           log global
           acl www hdr_reg(host) -i www.luffycity.org
           use_backend www.luffycity.com if www
   
   backend www.luffycity.com
           server 100.1.7.9 100.1.7.9 weight 20 maxconn 3000

请将文件中的 luffycity修改为 pythonav 。

"""
- 文件读到内存，再通过replace（适用于小文件，不适用大文件）
- 挨个位置读文件的内容，遇到luffycity将其替换成pythonav。（不可取）
- 同时打开两个文件，读+写。（适用于小文件，适用大文件）
"""
wit h open('files/ha.conf', mode='r', encoding='utf-8') as read_file_object, open('files/new.conf', mode='w',
                                                                                 encoding='utf-8') as write_file_object:
    for line in read_file_object:
        new_line = line.replace("luffycity", 'pythonav')
        write_file_object.write(new_line)

# 重命名
import shutil

shutil.move("files/new.conf", 'files/ha.conf')

2. csv格式文件

逗号分隔值（Comma-Separated Values，CSV，有时也称为字符分隔值，因为分隔字符也可以不是逗号），其文件以纯文本形式存储表格数据（数字和文本）。

对于这种格式的数据，我们需要利用open函数来读取文件并根据逗号分隔的特点来进行处理。

股票代码,股票名称,当前价,涨跌额,涨跌幅,年初至今
SH601778,N晶科,6.29,+1.92,-43.94%,+43.94%
SH688566,吉贝尔,52.66,+6.96,+15.23%,+122.29%

练习题案例：下载文档中的所有图片且以用户名为图片名称存储。

ID,用户名,头像
26044585,Hush,https://hbimg.huabanimg.com/51d46dc32abe7ac7f83b94c67bb88cacc46869954f478-aP4Q3V
19318369,柒十一,https://hbimg.huabanimg.com/703fdb063bdc37b11033ef794f9b3a7adfa01fd21a6d1-wTFbnO
15529690,Law344,https://hbimg.huabanimg.com/b438d8c61ed2abf50ca94e00f257ca7a223e3b364b471-xrzoQd
18311394,Jennah·,https://hbimg.huabanimg.com/4edba1ed6a71797f52355aa1de5af961b85bf824cb71-px1nZz
18009711,可洛爱画画,https://hbimg.huabanimg.com/03331ef39b5c7687f5cc47dbcbafd974403c962ae88ce-Co8AUI
30574436,花姑凉~,https://hbimg.huabanimg.com/2f5b657edb9497ff8c41132e18000edb082d158c2404-8rYHbw
17740339,小巫師,https://hbimg.huabanimg.com/dbc6fd49f1915545cc42c1a1492a418dbaebd2c21bb9-9aDqgl
```python
import os
import requests

with open('files/mv.csv', mode='r', encoding='utf-8') as file_object:
    file_object.readline()
    for line in file_object:
        user_id, username, url = line.strip().split(',')
        print(username, url)
        # 1.根据URL下载图片
        res = requests.get(
            url=url,
            headers={
    
    
                "User-Agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36"
            }
        )
        # 检查images目录是否存在？不存在，则创建images目录
        if not os.path.exists("images"):
            # 创建images目录
            os.makedirs("images")

        # 2.将图片的内容写入到文件
        with open("images/{}.png".format(username), mode='wb') as img_object:
            img_object.write(res.content)

3.ini格式文件

ini文件是Initialization File的缩写，平时用于存储软件的的配置文件。例如：MySQL数据库的配置文件。

[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
log-bin=py-mysql-bin
character-set-server=utf8
collation-server=utf8_general_ci
log-error=/var/log/mysqld.log
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0

[mysqld_safe]
log-error=/var/log/mariadb/mariadb.log
pid-file=/var/run/mariadb/mariadb.pid

[client]
default-character-set=utf8

这种格式是可以直接使用open来出来，考虑到自己处理比较麻烦，所以Python为我们提供了更为方便的方式。

import configparser

config = configparser.ConfigParser()
config.read('files/my.ini', encoding='utf-8')
# config.read('/Users/wupeiqi/PycharmProjects/luffyCourse/day09/files/my.ini', encoding='utf-8')

# 1.获取所有的节点
"""
result = config.sections()
print(result)  # ['mysqld', 'mysqld_safe', 'client']
"""

# 2.获取节点下的键值
"""
result = config.items("mysqld_safe")
print(result)  # [('log-error', '/var/log/mariadb/mariadb.log'), ('pid-file', '/var/run/mariadb/mariadb.pid')]

for key, value in config.items("mysqld_safe"):
    print(key, value)
"""

# 3.获取某个节点下的键对应的值
"""
result = config.get("mysqld","collation-server")
print(result)
"""

# 4.其他

# 4.1 是否存在节点
# v1 = config.has_section("client")
# print(v1)

# 4.2 添加一个节点
# config.add_section("group")     #只是添加在内训中，要看到这个节点需要写入
# config.set('group','name','zhangsan')
# config.set('client','name','zhangsan')
# config.write(open('files/new.ini', mode='w', encoding='utf-8'))

# 4.3 删除
# config.remove_section('client')
# config.remove_option("mysqld", "datadir")
# config.write(open('files/new.ini', mode='w', encoding='utf-8'))

读取所有节点

import configparser

config = configparser.ConfigParser()
config.read('/Users/wupeiqi/PycharmProjects/luffyCourse/day09/files/my.conf', encoding='utf-8')
# config.read('my.conf', encoding='utf-8')
ret = config.sections()
print(ret) 

>>输出
['mysqld', 'mysqld_safe', 'client']

读取节点下的键值

import configparser

config = configparser.ConfigParser()
config.read('/Users/wupeiqi/PycharmProjects/luffyCourse/day09/files/my.conf', encoding='utf-8')
# config.read('my.conf', encoding='utf-8')
item_list = config.items("mysqld_safe")
print(item_list) 

>>输出
[('log-error', '/var/log/mariadb/mariadb.log'), ('pid-file', '/var/run/mariadb/mariadb.pid')]

读取节点下值（根据节点+键）

import configparser

config = configparser.ConfigParser()
config.read('/Users/wupeiqi/PycharmProjects/luffyCourse/day09/files/my.conf', encoding='utf-8')

value = config.get('mysqld', 'log-bin')
print(value)

>>输出
py-mysql-bin

检查、删除、添加节点

import configparser

config = configparser.ConfigParser()
config.read('/Users/wupeiqi/PycharmProjects/luffyCourse/day09/files/my.conf', encoding='utf-8')
# config.read('my.conf', encoding='utf-8')


# 检查
has_sec = config.has_section('mysqld')
print(has_sec)

# 添加节点
config.add_section("SEC_1")
# 节点中设置键值
config.set('SEC_1', 'k10', "123")
config.set('SEC_1', 'name', "哈哈哈哈哈")

config.add_section("SEC_2")
config.set('SEC_2', 'k10', "123")
# 内容写入新文件
config.write(open('/Users/wupeiqi/PycharmProjects/luffyCourse/day09/files/xxoo.conf', 'w'))


# 删除节点
config.remove_section("SEC_2")
# 删除节点中的键值
config.remove_option('SEC_1', 'k10')
config.write(open('/Users/wupeiqi/PycharmProjects/luffyCourse/day09/files/new.conf', 'w'))

4.XML格式文件（使用不多）

可扩展标记语言，是一种简单的数据存储语言，XML 被设计用来传输和存储数据。

存储，可用来存放配置文件，例如：java的配置文件。
传输，网络传输时以这种格式存在，例如：早期ajax传输的数据、soap协议等。

<data>
    <country name="Liechtenstein">
        <rank updated="yes">2</rank>
        <year>2023</year>
        <gdppc>141100</gdppc>
        <neighbor direction="E" name="Austria" />
        <neighbor direction="W" name="Switzerland" />
    </country>
    <country name="Singapore">
        <rank updated="yes">5</rank>
        <year>2026</year>
        <gdppc>59900</gdppc>
        <neighbor direction="N" name="Malaysia" />
    </country>
    <country name="Panama">
        <rank updated="yes">69</rank>
        <year>2026</year>
        <gdppc>13600</gdppc>
        <neighbor direction="W" name="Costa Rica" />
        <neighbor direction="E" name="Colombia" />
    </country>
</data>

注意：在Python开发中用的相对来比较少，大家作为了解即可（后期课程在讲解微信支付、微信公众号消息处理时会用到基于xml传输数据）。

例如：https://developers.weixin.qq.com/doc/offiaccount/Message_Management/Receiving_standard_messages.html

【1】读取文件和内容

from xml.etree import ElementTree as ET

# ET去打开xml文件
tree = ET.parse("files/xo.xml")

# 获取根标签
root = tree.getroot()

print(root) # <Element 'data' at 0x7f94e02763b0>

from xml.etree import ElementTree as ET

content = """
<data>
    <country name="Liechtenstein">
        <rank updated="yes">2</rank>
        <year>2023</year>
        <gdppc>141100</gdppc>
        <neighbor direction="E" name="Austria" />
        <neighbor direction="W" name="Switzerland" />
    </country>
     <country name="Panama">
        <rank updated="yes">69</rank>
        <year>2026</year>
        <gdppc>13600</gdppc>
        <neighbor direction="W" name="Costa Rica" />
        <neighbor direction="E" name="Colombia" />
    </country>
</data>
"""

root = ET.XML(content)
print(root)  # <Element 'data' at 0x7fdaa019cea0>

【2】读取节点数据

from xml.etree import ElementTree as ET

content = """
<data>
    <country name="Liechtenstein" id="999" >
        <rank>2</rank>
        <year>2023</year>
        <gdppc>141100</gdppc>
        <neighbor direction="E" name="Austria" />
        <neighbor direction="W" name="Switzerland" />
    </country>
     <country name="Panama">
        <rank>69</rank>
        <year>2026</year>
        <gdppc>13600</gdppc>
        <neighbor direction="W" name="Costa Rica" />
        <neighbor direction="E" name="Colombia" />
    </country>
</data>
"""

# 获取根标签 data
root = ET.XML(content)

country_object = root.find("country")
print(country_object.tag, country_object.attrib)
gdppc_object = country_object.find("gdppc")
print(gdppc_object.tag,gdppc_object.attrib,gdppc_object.text)

from xml.etree import ElementTree as ET

content = """
<data>
    <country name="Liechtenstein">
        <rank>2</rank>
        <year>2023</year>
        <gdppc>141100</gdppc>
        <neighbor direction="E" name="Austria" />
        <neighbor direction="W" name="Switzerland" />
    </country>
     <country name="Panama">
        <rank>69</rank>
        <year>2026</year>
        <gdppc>13600</gdppc>
        <neighbor direction="W" name="Costa Rica" />
        <neighbor direction="E" name="Colombia" />
    </country>
</data>
"""

# 获取根标签 data
root = ET.XML(content)

# 获取data标签的孩子标签
for child in root:
    # child.tag = conntry
    # child.attrib = {"name":"Liechtenstein"}
    print(child.tag, child.attrib)
    for node in child:
        print(node.tag, node.attrib, node.text)

from xml.etree import ElementTree as ET

content = """
<data>
    <country name="Liechtenstein">
        <rank>2</rank>
        <year>2023</year>
        <gdppc>141100</gdppc>
        <neighbor direction="E" name="Austria" />
        <neighbor direction="W" name="Switzerland" />
    </country>
     <country name="Panama">
        <rank>69</rank>
        <year>2026</year>
        <gdppc>13600</gdppc>
        <neighbor direction="W" name="Costa Rica" />
        <neighbor direction="E" name="Colombia" />
    </country>
</data>
"""

root = ET.XML(content)

for child in root.iter('year'):
    print(child.tag, child.text)

from xml.etree import ElementTree as ET

content = """
<data>
    <country name="Liechtenstein">
        <rank>2</rank>
        <year>2023</year>
        <gdppc>141100</gdppc>
        <neighbor direction="E" name="Austria" />
        <neighbor direction="W" name="Switzerland" />
    </country>
     <country name="Panama">
        <rank>69</rank>
        <year>2026</year>
        <gdppc>13600</gdppc>
        <neighbor direction="W" name="Costa Rica" />
        <neighbor direction="E" name="Colombia" />
    </country>
</data>
"""

root = ET.XML(content)
v1 = root.findall('country')
print(v1)

v2 = root.find('country').find('rank')
print(v2.text)

【3】修改和删除节点

from xml.etree import ElementTree as ET

content = """
<data>
    <country name="Liechtenstein">
        <rank>2</rank>
        <year>2023</year>
        <gdppc>141100</gdppc>
        <neighbor direction="E" name="Austria" />
        <neighbor direction="W" name="Switzerland" />
    </country>
     <country name="Panama">
        <rank>69</rank>
        <year>2026</year>
        <gdppc>13600</gdppc>
        <neighbor direction="W" name="Costa Rica" />
        <neighbor direction="E" name="Colombia" />
    </country>
</data>
"""

root = ET.XML(content)

# 修改节点内容和属性（此处只是在内存中修改，若要显示出来，应通过下方的方法保存）
rank = root.find('country').find('rank')
print(rank.text)
rank.text = "999"
rank.set('update', '2020-11-11')
print(rank.text, rank.attrib)
############ 保存文件 ############
tree = ET.ElementTree(root)
tree.write("new.xml", encoding='utf-8')


# 删除节点
root.remove( root.find('country') )
print(root.findall('country'))

############ 保存文件 ############
tree = ET.ElementTree(root)
tree.write("newnew.xml", encoding='utf-8')

【4】构建文档

<home>
    <son name="儿1">
        <grandson name="儿11"></grandson>
        <grandson name="儿12"></grandson>
    </son>
    <son name="儿2"></son>
</home>

from xml.etree import ElementTree as ET

# 创建根标签
root = ET.Element("home")

# 创建节点大儿子
son1 = ET.Element('son', {
    
    'name': '儿1'})
# 创建小儿子
son2 = ET.Element('son', {
    
    "name": '儿2'})

# 在大儿子中创建两个孙子
grandson1 = ET.Element('grandson', {
    
    'name': '儿11'})
grandson2 = ET.Element('grandson', {
    
    'name': '儿12'})
son1.append(grandson1)
son1.append(grandson2)

# 把儿子添加到根节点中
root.append(son1)
root.append(son2)

tree = ET.ElementTree(root)
tree.write('oooo.xml', encoding='utf-8', short_empty_elements=False)

<famliy>
    <son name="儿1">
        <grandson name="儿11"></grandson>
        <grandson name="儿12"></grandson>
    </son>
    <son name="儿2"></son>
</famliy>

from xml.etree import ElementTree as ET

# 创建根节点
root = ET.Element("famliy")


# 创建大儿子
son1 = root.makeelement('son', {
    
    'name': '儿1'})
# 创建小儿子
son2 = root.makeelement('son', {
    
    "name": '儿2'})

# 在大儿子中创建两个孙子
grandson1 = son1.makeelement('grandson', {
    
    'name': '儿11'})
grandson2 = son1.makeelement('grandson', {
    
    'name': '儿12'})

son1.append(grandson1)
son1.append(grandson2)


# 把儿子添加到根节点中
root.append(son1)
root.append(son2)

tree = ET.ElementTree(root)
tree.write('oooo.xml',encoding='utf-8')

<famliy>
	<son name="儿1">
    	<age name="儿11">孙子</age>
    </son>
	<son name="儿2"></son>
</famliy>

from xml.etree import ElementTree as ET


# 创建根节点
root = ET.Element("famliy")


# 创建节点大儿子
son1 = ET.SubElement(root, "son", attrib={
    
    'name': '儿1'})
# 创建小儿子
son2 = ET.SubElement(root, "son", attrib={
    
    "name": "儿2"})

# 在大儿子中创建一个孙子
grandson1 = ET.SubElement(son1, "age", attrib={
    
    'name': '儿11'})
grandson1.text = '孙子'


et = ET.ElementTree(root)  #生成文档对象
et.write("test.xml", encoding="utf-8")

<user><![CDATA[你好呀]]</user>

from xml.etree import ElementTree as ET

# 创建根节点
root = ET.Element("user")
root.text = "<![CDATA[你好呀]]"

et = ET.ElementTree(root)  # 生成文档对象
et.write("test.xml", encoding="utf-8")

案例：

content = """<xml>
    <ToUserName><![CDATA[gh_7f083739789a]]></ToUserName>
    <FromUserName><![CDATA[oia2TjuEGTNoeX76QEjQNrcURxG8]]></FromUserName>
    <CreateTime>1395658920</CreateTime>
    <MsgType><![CDATA[event]]></MsgType>
    <Event><![CDATA[TEMPLATESENDJOBFINISH]]></Event>
    <MsgID>200163836</MsgID>
    <Status><![CDATA[success]]></Status>
</xml>"""

from xml.etree import ElementTree as ET

info = {
    
    }
root = ET.XML(content)
for node in root:
    # print(node.tag,node.text)
    info[node.tag] = node.text
print(info)

5.Excel格式文件

Python内部未提供处理Excel文件的功能，想要在Python中操作Excel需要按照第三方的模块。

pip install openpyxl

此模块中集成了Python操作Excel的相关功能，接下来我们就需要去学习该模块提供的相关功能即可。

【1】读Excel（了解即可）

读sheet

from openpyxl import load_workbook

wb = load_workbook("files/p1.xlsx")

# sheet相关操作

# 1.获取excel文件中的所有sheet名称

print(wb.sheetnames) # 获取所有的sheet名名称['数据导出', '用户列表', 'Sheet1', 'Sheet2']


# 2.选择sheet，基于sheet名称

sheet = wb["数据导出"]
cell = sheet.cell(1, 2)
print(cell.value)


# 3.选择sheet，基于索引位置

sheet = wb.worksheets[0]
cell = sheet.cell(1,2)
print(cell.value)
"""

# 4.循环所有的sheet
"""
for name in wb.sheetnames:
    sheet = wb[name]
    cell = sheet.cell(1, 1)
    print(cell.value)
"""
"""
for sheet in wb.worksheets:
    cell = sheet.cell(1, 1)
    print(cell.value)
"""
"""
for sheet in wb:
    cell = sheet.cell(1, 1)
    print(cell.value)
"""

读sheet中单元格的数据

from openpyxl import load_workbook

wb = load_workbook("files/p1.xlsx")
sheet = wb.worksheets[0]

# 1.获取第N行第N列的单元格(位置是从1开始）
"""
cell = sheet.cell(1, 1)

print(cell.value)
print(cell.style)
print(cell.font)
print(cell.alignment)
"""

# 2.获取某个单元格
"""
c1 = sheet["A2"]
print(c1.value)

c2 = sheet['D4']
print(c2.value)
"""

# 3.第N行所有的单元格
"""
for cell in sheet[1]:
    print(cell.value)
"""

# 4.所有行的数据（获取某一列数据）
"""
for row in sheet.rows:
    print(row[0].value, row[1].value)
"""

# 5.获取所有列的数据
"""
for col in sheet.columns:
    print(col[1].value)
"""

读合并的单元格

from openpyxl import load_workbook

wb = load_workbook("files/p1.xlsx")
sheet = wb.worksheets[2]

# 获取第N行第N列的单元格(位置是从1开始）
c1 = sheet.cell(1, 1)
print(c1)  # <Cell 'Sheet1'.A1>
print(c1.value) # 用户信息

c2 = sheet.cell(1, 2)
print(c2)  # <MergedCell 'Sheet1'.B1>
print(c2.value) # None

from openpyxl import load_workbook

wb = load_workbook('files/p1.xlsx')
sheet = wb.worksheets[2]
for row in sheet.rows:
    print(row)

>>> 输出结果
(<Cell 'Sheet1'.A1>, <MergedCell 'Sheet1'.B1>, <Cell 'Sheet1'.C1>)
(<Cell 'Sheet1'.A2>, <Cell 'Sheet1'.B2>, <Cell 'Sheet1'.C2>)
(<Cell 'Sheet1'.A3>, <Cell 'Sheet1'.B3>, <Cell 'Sheet1'.C3>)
(<MergedCell 'Sheet1'.A4>, <Cell 'Sheet1'.B4>, <Cell 'Sheet1'.C4>)
(<Cell 'Sheet1'.A5>, <Cell 'Sheet1'.B5>, <Cell 'Sheet1'.C5>)

【2】写Excel

在Excel中想要写文件，大致要分为在：

原Excel文件基础上写内容。

from openpyxl import load_workbook

wb = load_workbook('files/p1.xlsx')
sheet = wb.worksheets[0]

# 找到单元格，并修改单元格的内容
cell = sheet.cell(1, 1)
cell.value = "新的开始"

# 将excel文件保存到p2.xlsx文件中
wb.save("files/p2.xlsx")

新创建Excel文件写内容。

from openpyxl import workbook

# 创建excel且默认会创建一个sheet（名称为Sheet）
wb = workbook.Workbook()

sheet = wb.worksheets[0] # 或 sheet = wb["Sheet"]

# 找到单元格，并修改单元格的内容
cell = sheet.cell(1, 1)
cell.value = "新的开始"

# 将excel文件保存到p2.xlsx文件中
wb.save("files/p2.xlsx")

在了解了如何读取Excel和创建Excel之后，后续对于Excel中的sheet和cell操作基本上都相同。

from openpyxl import workbook

wb = workbook.Workbook() # Sheet

# 1. 修改sheet名称
"""
sheet = wb.worksheets[0]
sheet.title = "数据集"
wb.save("p2.xlsx")
"""

# 2. 创建sheet并设置sheet颜色
"""
sheet = wb.create_sheet("工作计划", 0)
sheet.sheet_properties.tabColor = "1072BA"
wb.save("p2.xlsx")
"""

# 3. 默认打开的sheet
"""
wb.active = 0
wb.save("p2.xlsx")
"""

# 4. 拷贝sheet
"""
sheet = wb.create_sheet("工作计划")
sheet.sheet_properties.tabColor = "1072BA"

new_sheet = wb.copy_worksheet(wb["Sheet"])
new_sheet.title = "新的计划"
wb.save("p2.xlsx")
"""

# 5.删除sheet
"""
del wb["用户列表"]
wb.save('files/p2.xlsx')
"""

from openpyxl import load_workbook
from openpyxl.styles import Alignment, Border, Side, Font, PatternFill, GradientFill


wb = load_workbook('files/p1.xlsx')

sheet = wb.worksheets[1]

# 1. 获取某个单元格，修改值
"""
cell = sheet.cell(1, 1)
cell.value = "开始"
wb.save("p2.xlsx")
"""

# 2.  获取某个单元格，修改值
"""
sheet["B3"] = "Alex"
wb.save("p2.xlsx")
"""

# 3. 获取某些单元格，修改值
"""
cell_list = sheet["B2":"C3"]
for row in cell_list:
    for cell in row:
        cell.value = "新的值"
wb.save("p2.xlsx")
"""

# 4. 对齐方式
"""
cell = sheet.cell(1, 1)

# horizontal，水平方向对齐方式："general", "left", "center", "right", "fill", "justify", "centerContinuous", "distributed"
# vertical，垂直方向对齐方式："top", "center", "bottom", "justify", "distributed"
# text_rotation，旋转角度。
# wrap_text，是否自动换行。
cell.alignment = Alignment(horizontal='center', vertical='distributed', text_rotation=45, wrap_text=True)
wb.save("p2.xlsx")
"""

# 5. 边框
# side的style有如下：dashDot','dashDotDot', 'dashed','dotted','double','hair', 'medium', 'mediumDashDot', 'mediumDashDotDot','mediumDashed', 'slantDashDot', 'thick', 'thin'
"""
cell = sheet.cell(9, 2)
cell.border = Border(
    top=Side(style="thin", color="FFB6C1"), 
    bottom=Side(style="dashed", color="FFB6C1"),
    left=Side(style="dashed", color="FFB6C1"),
    right=Side(style="dashed", color="9932CC"),
    diagonal=Side(style="thin", color="483D8B"),  # 对角线
    diagonalUp=True,  # 左下 ~ 右上
    diagonalDown=True  # 左上 ~ 右下
)
wb.save("p2.xlsx")
"""

# 6.字体
"""
cell = sheet.cell(5, 1)
cell.font = Font(name="微软雅黑", size=45, color="ff0000", underline="single")
wb.save("p2.xlsx")
"""

# 7.背景色
"""
cell = sheet.cell(5, 3)
cell.fill = PatternFill("solid", fgColor="99ccff")
wb.save("p2.xlsx")
"""

# 8.渐变背景色
"""
cell = sheet.cell(5, 5)
cell.fill = GradientFill("linear", stop=("FFFFFF", "99ccff", "000000"))
wb.save("p2.xlsx")
"""

# 9.宽高（索引从1开始）
"""
sheet.row_dimensions[1].height = 50
sheet.column_dimensions["E"].width = 100
wb.save("p2.xlsx")
"""

# 10.合并单元格
"""
sheet.merge_cells("B2:D8")
sheet.merge_cells(start_row=15, start_column=3, end_row=18, end_column=8)
wb.save("p2.xlsx")
"""
"""
sheet.unmerge_cells("B2:D8")
wb.save("p2.xlsx")
"""

# 11.写入公式
"""
sheet = wb.worksheets[3]
sheet["D1"] = "合计"
sheet["D2"] = "=B2*C2"
wb.save("p2.xlsx")
"""
"""
sheet = wb.worksheets[3]
sheet["D3"] = "=SUM(B3,C3)"
wb.save("p2.xlsx")
"""

# 12.删除
"""
# idx，要删除的索引位置
# amount，从索引位置开始要删除的个数（默认为1）
sheet.delete_rows(idx=1, amount=20)
sheet.delete_cols(idx=1, amount=3)
wb.save("p2.xlsx")
"""

# 13.插入
"""
sheet.insert_rows(idx=5, amount=10)
sheet.insert_cols(idx=3, amount=2)
wb.save("p2.xlsx")
"""

# 14.循环写内容
"""
sheet = wb["Sheet"]
cell_range = sheet['A1:C2']
for row in cell_range:
    for cell in row:
        cell.value = "xx"

for row in sheet.iter_rows(min_row=5, min_col=1, max_col=7, max_row=10):
    for cell in row:
        cell.value = "oo"
wb.save("p2.xlsx")
"""

# 15.移动
"""
# 将H2:J10范围的数据，向右移动15个位置、向上移动1个位置
sheet.move_range("H2:J10",rows=1, cols=15)
wb.save("p2.xlsx")
"""
"""
sheet = wb.worksheets[3]
sheet["D1"] = "合计"
sheet["D2"] = "=B2*C2"
sheet["D3"] = "=SUM(B3,C3)"
sheet.move_range("B1:D3",cols=10, translate=True) # 自动翻译公式
wb.save("p2.xlsx")
"""

# 16.打印区域
"""
sheet.print_area = "A1:D200"
wb.save("p2.xlsx")
"""

# 17.打印时，每个页面的固定表头
"""
sheet.print_title_cols = "A:D"
sheet.print_title_rows = "1:3"
wb.save("p2.xlsx")
"""

6.压缩文件

基于Python内置的shutil模块可以实现对压缩文件的操作。

import shutil

# 1. 压缩文件
"""
# base_name，压缩后的压缩包文件
# format，压缩的格式，例如："zip", "tar", "gztar", "bztar", or "xztar".
# root_dir，要压缩的文件夹路径
"""
# shutil.make_archive(base_name=r'datafile',format='zip',root_dir=r'files')


# 2. 解压文件
"""
# filename，要解压的压缩包文件
# extract_dir，解压的路径
# format，压缩文件格式
"""
# shutil.unpack_archive(filename=r'datafile.zip', extract_dir=r'xxxxxx/xo', format='zip')

7.路径相关

【1】转义

windows路径使用的是\，linux路径使用的是/。

特别的，在windows系统中如果有这样的一个路径 D:\nxxx\txxx\x1，程序会报错。因为在路径中存在特殊符 \n（换行符）和\t（制表符），Python解释器无法自动区分。

所以，在windows中编写路径时，一般有两种方式：

加转义符，例如："D:\\nxxx\\txxx\\x1"
路径前加r，例如：r"D:\\nxxx\\txxx\\x1"

【2】程序当前路径

项目中如果使用了相对路径，那么一定要注意当前所在的位置。

例如：在/Users/wupeiqi/PycharmProjects/CodeRepository/路径下编写 demo.py文件

with open("a1.txt", mode='w', encoding='utf-8') as f:
    f.write("你好呀")

用以下两种方式去运行：

方式1，文件会创建在 /Users/wupeiqi/PycharmProjects/CodeRepository/ 目录下。

cd /Users/wupeiqi/PycharmProjects/CodeRepository/
python demo.py

方式2，文件会创建在 /Users/wupeiqi目录下。

cd /Users/wupeiqi
python /Users/wupeiqi/PycharmProjects/CodeRepository/demo.py

import os

"""
# 1.获取当前运行的py脚本所在路径
abs = os.path.abspath(__file__)
print(abs) # /Users/wupeiqi/PycharmProjects/luffyCourse/day09/20.路径相关.py
path = os.path.dirname(abs)
print(path) # /Users/wupeiqi/PycharmProjects/luffyCourse/day09
"""
base_dir = os.path.dirname(os.path.abspath(__file__))
file_path = os.path.join(base_dir, 'files', 'info.txt')   # 根据系统的不同，对路径的书写格式进行更改
print(file_path)
if os.path.exists(file_path):
    file_object = open(file_path, mode='r', encoding='utf-8')
    data = file_object.read()
    file_object.close()

    print(data)
else:
    print('文件路径不存在')

【3】文件和路径相关

import shutil
import os

# 1. 获取当前脚本绝对路径
"""
abs_path = os.path.abspath(__file__)
print(abs_path)
"""

# 2. 获取当前文件的上级目录
"""
base_path = os.path.dirname( os.path.dirname(路径) ） 
print(base_path)
"""

# 3. 路径拼接
"""
p1 = os.path.join(base_path, 'xx')   
print(p1)

p2 = os.path.join(base_path, 'xx', 'oo', 'a1.png')
print(p2)
"""

# 4. 判断路径是否存在
"""
exists = os.path.exists(p1)
print(exists)
"""

# 5. 创建文件夹
"""
os.makedirs(路径)
"""
"""
path = os.path.join(base_path, 'xx', 'oo', 'uuuu')
if not os.path.exists(path):
    os.makedirs(path)
"""

# 6. 是否是文件夹
"""
file_path = os.path.join(base_path, 'xx', 'oo', 'uuuu.png')
is_dir = os.path.isdir(file_path)
print(is_dir) # False，最后一个文件有后缀名，故判断为不是文件夹

folder_path = os.path.join(base_path, 'xx', 'oo', 'uuuu')
is_dir = os.path.isdir(folder_path)
print(is_dir) # True

"""

# 7. 删除文件或文件夹
"""
os.remove("文件路径")
"""
"""
path = os.path.join(base_path, 'xx')
shutil.rmtree(path)
"""

# 8. 拷贝文件夹
"""
shutil.copytree("/Users/wupeiqi/Desktop/图/csdn/","/Users/wupeiqi/PycharmProjects/CodeRepository/files")
                    #  要拷贝的文件夹                    拷贝到此处
"""

# 9.拷贝文件
"""
shutil.copy("/Users/wupeiqi/Desktop/图/csdn/[email protected]","/Users/wupeiqi/PycharmProjects/CodeRepository/")
shutil.copy("/Users/wupeiqi/Desktop/图/csdn/[email protected]","/Users/wupeiqi/PycharmProjects/CodeRepository/x.png")
"""

# 10.文件或文件夹重命名
"""
shutil.move("/Users/wupeiqi/PycharmProjects/CodeRepository/x.png","/Users/wupeiqi/PycharmProjects/CodeRepository/xxxx.png")
shutil.move("/Users/wupeiqi/PycharmProjects/CodeRepository/files","/Users/wupeiqi/PycharmProjects/CodeRepository/images")
"""

总结

文件相对路径，在使用相对路径时可能会执行程序的目录不同，导致路径出问题。所以，如若使用相对路径请务必清楚当前运行程序所在目录。
文件绝对路径（推荐），不要将文件路径写死，而是基于 os 模块中的相关功能自动化获取绝对路径，以方便项目移动到其他文件或电脑上。

   import os
   base_dir = os.path.dirname(os.path.abspath(__file__))
   file_path = os.path.join(base_dir, 'files', 'info.txt')

路径转义
- 手动写路径，需要自己在路径中添加 r 或加入 \ 来进行处理。
- 基于os.path.join拼接，内部自动处理，不需要手动处理。
如何去下载安装第三方模块？

   pip install 模块名称

requests模块，可以用来发送网络请求。
openpyxl模块，处理Excel格式的文件。

知识点补充

# 1.for循环

data_list = [11,22,33,44,55]
for item in data_list:
    print(item)
    break
else:
    print("else中的内容") # for循环中的内容全部执行了一遍，且未遇到break，则会执行else中的内容


# 2.enumerate  循环内容，循环索引

# 方法一（旧方法）:
data_list = [11, 22, 33, 44, 55]
for index in range(len(data_list)):
    print(index+1, data_list[index])

# 方法二:
data_list = [11, 22, 33, 44, 55]
for i, item in enumerate(data_list, 1):   #  I从1开始每次加1，i也可以是其他数值
    print(i, item)

# 输出：
1 11
2 22
3 33 
4 44
5 55

作业

基于csv格式实现用户的注册 & 登录认证。详细需求如下：
- 用户注册时，新注册用户要写入文件csv文件中，输入Q或q则退出。
- 用户登录时，逐行读取csv文件中的用户信息并进行校验。
- 提示：文件路径须使用os模块构造的绝对路径的方式。

import os

# 文件路径处理
base_dir = os.path.dirname(os.path.abspath(__file__))
db_file_path = os.path.join(base_dir, 'db.csv')

# 用户注册
while True:
    choice = input("是否进行用户注册（Y/N）？")
    choice = choice.upper()
    if choice not in {
    
    'Y', 'N'}:
        print('输入格式错误，请重新输入。')
        continue

    if choice == "N":
        break

    with open(db_file_path, mode='a', encoding='utf-8') as file_object:
        while True:
            user = input("请输入用户名（Q/q退出）：")
            if user.upper() == 'Q':
                break
            pwd = input("请输入密码：")
            file_object.write("{},{}\n".format(user, pwd))
            file_object.flush()
    break

# 用户登录
print("欢迎使用xx系统，请登录！")
username = input("请输入用户名：")
password = input("请输入密码：")
if not os.path.exists(db_file_path):
    print("用户文件不存在")
else:
    with open(db_file_path, mode='r', encoding='utf-8') as file_object:
        for line in file_object:
            user, pwd = line.strip().split(',')
            if username == user and pwd == password:
                print('登录成功')
                break
        else:
            print("用户名或密码错误")
"""

补充代码：实现去网上获取指定地区的天气信息，并写入到Excel中。

   import requests
   
   while True:
       city = input("请输入城市（Q/q退出）：")
       if city.upper() == "Q":
           break
       url = "http://ws.webxml.com.cn//WebServices/WeatherWebService.asmx/getWeatherbyCityName?theCityName={}".format(city)
       res = requests.get(url=url)
       print（res.text）
   
       # 1.提取XML格式中的数据
       # 2.为每个城市创建一个sheet，并将获取的xml格式中的数据写入到excel中。

import os
import requests
from xml.etree import ElementTree as ET
from openpyxl import workbook

# 处理文件路径
base_dir = os.path.dirname(os.path.abspath(__file__))
target_excel_file_path = os.path.join(base_dir, 'weather.xlsx')

# 创建excel且默认会创建一个sheet（名称为Sheet）
wb = workbook.Workbook()
del wb['Sheet']

while True:
    # 用户输入城市，并获取该城市的天气信息
    city = input("请输入城市（Q/q退出）：")
    if city.upper() == "Q":
        break
    url = "http://ws.webxml.com.cn//WebServices/WeatherWebService.asmx/getWeatherbyCityName?theCityName={}".format(city)
    res = requests.get(url=url)

    # 1.提取XML格式中的数据
    root = ET.XML(res.text)

    # 2.为每个城市创建一个sheet，并将获取的xml格式中的数据写入到excel中。
    sheet = wb.create_sheet(city)

    for row_index, node in enumerate(root, 1):
        text = node.text
        cell = sheet.cell(row_index, 1)
        cell.value = text

wb.save(target_excel_file_path)

读取ini文件内容，按照规则写入到Excel中。
- ini文件内容如下：

 [mysqld]
 datadir=/var/lib/mysql
 socket=/var/lib/mysql/mysql.sock
 log-bin=py-mysql-bin
 character-set-server=utf8
 collation-server=utf8_general_ci
 log-error=/var/log/mysqld.log
 # Disabling symbolic-links is recommended to prevent assorted security risks
 symbolic-links=0
 
 [mysqld_safe]
 log-error=/var/log/mariadb/mariadb.log
 pid-file=/var/run/mariadb/mariadb.pid
 
 [client]
 default-character-set=utf8

读取ini格式的文件，并创建一个excel文件，且为每个节点创建一个sheet，然后将节点下的键值写入到excel中，按照如下格式。
- 首行，字体白色 & 单元格背景色蓝色。
- 内容均居中。
- 边框。

import os
import configparser
from openpyxl import workbook
from openpyxl.styles import Alignment, Border, Side, Font, PatternFill

# 文件路径处理
base_dir = os.path.dirname(os.path.abspath(__file__))
file_path = os.path.join(base_dir, 'files', 'my.ini')
target_excel_file_path = os.path.join(base_dir, 'my.xlsx')

# 创建excel且默认会创建一个sheet（名称为Sheet）
wb = workbook.Workbook()
del wb['Sheet']

# 解析ini格式文件
config = configparser.ConfigParser()
config.read(file_path, encoding='utf-8')

# 循环获取每个节点，并为每个节点创建一个sheet
for section in config.sections():
    # 在excel中创建一个sheet，名称为ini文件的节点名称
    sheet = wb.create_sheet(section)

    # 边框和居中（表头和内容都需要）
    side = Side(style="thin", color="000000")
    border = Border(top=side, bottom=side, left=side, right=side)

    align = Alignment(horizontal='center', vertical='center')

    # 为此在sheet设置表头
    title_dict = {
    
    "A1": "键", "B1": "值"}
    for position, text in title_dict.items():
        cell = sheet[position]
        # 设置值
        cell.value = text
        # 设置居中
        cell.alignment = align
        # 设置背景色
        cell.fill = PatternFill("solid", fgColor="6495ED")
        # 设置字体颜色
        cell.font = Font(name="微软雅黑", color="FFFFFF")
        # 设置边框
        cell.border = border

    # 读取此节点下的所有键值，并将键值写入到当前sheet中
    # row_index = 2
    # for key, val in config.items(section):
    #     c1 = sheet.cell(row_index, 1)
    #     c1.value = key
    #     c1.alignment = align
    #     c1.border = border
    #
    #     c2 = sheet.cell(row_index, 2)
    #     c2.value = val
    #     c2.alignment = align
    #     c2.border = border
    #     row_index += 1

    row_index = 2
    for group in config.items(section):
        # group = ("datadir","/var/lib/mysql")
        for col, text in enumerate(group, 1):
            cell = sheet.cell(row_index, col)
            cell.alignment = align
            cell.border = border
            cell.value = text
        row_index += 1

wb.save(target_excel_file_path)

补充代码，实现如下功能。

   import requests
   
   # 1.下载文件
   file_url = 'https://files.cnblogs.com/files/wupeiqi/HtmlStore.zip'
   res = requests.get(url=file_url)
   print(res.content)
   
   # 2.将下载的文件保存到当前执行脚本同级目录下 /files/package/ 目录下（且文件名为HtmlStore.zip）
   
   # 3.在将下载下来的文件解压到 /files/html/ 目录下

import os
import shutil
import requests

# 文件路径处理
base_dir = os.path.dirname(os.path.abspath(__file__))
download_folder = os.path.join(base_dir, 'files', 'package')
if not os.path.exists(download_folder):
    os.makedirs(download_folder)

# 1.下载文件
file_url = 'https://files.cnblogs.com/files/wupeiqi/HtmlStore.zip'
res = requests.get(url=file_url)

# 2.将下载的文件保存到当前执行脚本同级目录下 /files/package/ 目录下（且文件名为 HtmlStore.zip ）
file_name = file_url.split('/')[-1]
zip_file_path = os.path.join(download_folder, file_name) # .../files/package/HtmlStore.zip
with open(zip_file_path, mode='wb') as file_object:
    file_object.write(res.content)

# 3.在将下载下来的文件解压到 /files/html/ 目录下
unpack_folder = os.path.join(base_dir, 'files', 'html')
shutil.unpack_archive(filename=zip_file_path, extract_dir=unpack_folder, format='zip')