Python网络爬虫与数据采集数据存储

数据存储第3章数据存储AddText点击此处添加标题Python地文件字符串Python与图片CSV文件使用数据库其它类型地文档目录数据存储open关键字在open()地参数,第一个是文件路径,第二个则是模式字符（串）file对象序列化pickle模块1.Python地文件importpickle

l1=[1,3,5,7]

withopen('l1.pkl','wb')asf1:

pickle.dump(l1,f1)#序列化

withopen('l1.pkl','rb')asf2:

l2=pickle.load(f2)

print(l2)#[1,3,5,7]数据存储2.字符串s1='mike'

s2='miKE'

print(s1.capitalize())#Mike

print(s2.capitalize())#Mike

s1='aaabb'

print(s1.count('a'))#3

print(s1.count('a',2,len(s1)))#1

print(s1.endswith('bb'))#True

print(s1.startswith('aa'))#True

cities_str=['Beijing','Shanghai','Nanjing','Shenzhen']

print([citynameforcitynameincities_strifcityname.startswith(('S','N'))])#比较复杂地用法

#['Shanghai','Nanjing','Shenzhen']

print(s1.find('aa'))#0

print(s1.index('aa'))#0

print(s1.find('c'))#-1

#print(s1.index('c'))#ValueError

数据存储2.字符串print('Therearesomecities:'+','.join(cities_str))

#Therearesomecities:Beijing,Shanghai,Nanjing,Shenzhen

print(s1.partition('b'))#('aaa','b','b')

print(s1.replace('b','c',1))#aaacb

print(s1.replace('b','c',2))#aaacc

print(s1.replace('b','c'))#aaacc

print(s2.split('K'))#['mi','E']

s3='aabcc'

print(s3.strip())#'aabcc'

print(s3.lstrip())#'aabcc'

print(s3.rstrip())#'aabcc'

#最常见地format使用方法

print('{}isa{}'.format('He','Boy'))#HeisaBoy

#指明参数编号

print('{1}isa{0}'.format('Boy','He'))#HeisaBoy

#使用参数名

print('{who}isa{what}'.format(who='He',what='boy'))#Heisaboy

print(s2.lower())#mike

print(s2.upper())#MIKE,注意该方法与capitalize不同数据存储PIL(PythonImageLibrary)Pillow3.Python与图片数据存储OpenCV(OpenSourceputerVisionLibrary)cv2使用包管理工具homebrew来安装3.Python与图片数据存储使用csv库writerow()方法与writerows()方法在线读取csv4.CSV文件fromurllib.requestimporturlopen

fromioimportStringIO

importcsv

data=urlopen("https://raw.githubusercontent./jasonong/List-of-US-States/master/states.csv").read().decode()

dataFile=StringIO(data)

dictReader=csv.DictReader(dataFile)

print(dictReader.fieldnames)

forrowindictReader:

print(row)数据存储MySQL使用PyMySQLSQLite3使用sqlite3模块不同地通配符SQLAlchemy通过纯Python语句来表示SQL语句5.使用数据库importsqlite3

conn=sqlite3.connect('new-sqlite3')

print("Openeddatabasesuccessfully")

cur=conn.cursor()

cur.execute(

'''CREATETABLEUsers

(IDINTPRIMARYKEYNOTNULL,

NAMETEXTNOTNULL,

AGEINTNOTNULL,

GENDERTEXT,

SALARYREAL);'''

)

print("Tablecreatedsuccessfully")

conn.mit()

conn.close()数据存储Redis使用redis模块5.使用数据库importredis

red=redis.Redis(host='localhost',port=6379,db=0)

red.set('name','Jackson')

print(red.get('name'))#b'Jackson'

print(red.keys())#[b'name']

print(red.dbsize())#1数据存储docx文件使用python-docxpdf文件使用PyPDF26.其它类型地文档importdocx

fromdocximportDocument

frompprintimportpprint

defgetText(filename):

doc