re模块

# 1、\w
# print(re.findall(‘\w\w\w‘,"h ello 123_ (0"))
# h ello 123_ (0
#            \w\w\w

# 2. \W
# print(re.findall(‘\W‘,"h ello 123_ (0"))

# 3、\s
# print(re.findall(‘\s‘,"h e\tll\no 123_ (0"))
# print(re.findall(‘\w\s‘,"h ello 123_ (0"))

# 4、\S
# print(re.findall(‘\S‘,"h e\tll\no 123_ (0"))

# 5、\d
# print(re.findall(‘\d‘,"h e\tll\no 123_ (0"))

# 6、\D
# print(re.findall(‘\D‘,"h e\tll\no 123_ (0"))

# print(re.findall("a\db","a1b a2b a b aab aaaaaaaa1b a2c a22c a 3c"))
# a1b a2b a b aab aaaaaaaa1b a2c a22c a 3c
#                            a\db

# ["a1b","a2b","a1b"]

# 7、\n与\t
# msg="""h e\tll\n\no 123_ (0
# \t1
#     2
# 3
# """
# print(re.findall(‘\n‘,msg))
# print(re.findall(‘\t‘,msg))
# print(re.findall(‘ ‘,msg))


# 8、^与$
# print(re.findall("^egon","egon asdf 213123 egonafsadfegon"))
# egon asdf 213123 egonafsadfegon
# ^egon

# print(re.findall("egon$","egon asdf 213123 egonafsadfegon "))
#                                                        egon$


# print(re.findall("a\w\w\wc","ab12c3c a213c"))
# print(re.findall("^a\w\w\wc$","ab_2c"))

# 9、.与[]
# 9.1 .：代表匹配一个字符，该字符可以是任意字符
# print(re.findall("a\db","a1b a2b aab aaaaaaab a+b a-b a c"))
# print(re.findall("a\wb","a1b a2b aab aaaaaaab a+b a-b a c"))
# print(re.findall("a.b","a1b a2b aab aaaaaaab a+b a-b a b a c"))
# print(re.findall("a.b","a1b a2b aab aaaaaaab a\tb a-b a\nb a c",re.DOTALL))


# 9.2 []：代表匹配一个字符，我们可以指定该字符的范围
# print(re.findall("a[+-]b", "a1b a2b aab aaaaaaab a+b a-b a c"))
# print(re.findall("a[.*/+-]b", "a.b a2b a*b a/b aab aaaaaaab a+b a-b a c"))
# print(re.findall("a[a-z]b", "a.b a2b a*b a/b aab aaaaaaab a+b a-b a c")) # -放在[]内的开头或结果
# print(re.findall("a[a-zA-Z]b", "a.b a2b a*b a/b aAb aCb aab aaaaaaab a+b a-b a c")) # -放在[]内的开头或结果
# print(re.findall("a\db", "a.b a2b a*b a/b aAb aCb aab aaaaaaab a+b a-b a c")) # -放在[]内的开头或结果
# print(re.findall("a[0-9]b", "a.b a2b a*b a/b aAb aCb aab aaaaaaab a+b a-b a c")) # -放在[]内的开头或结果

# [^...]代表取反
# print(re.findall("a[^0-9]b", "a.b a2b a*b a/b aAb aCb aab aaaaaaab a+b a-b a c")) # -放在[]内的开头或结果

# 9.3 *: 左边那个字符出现0次或者无穷次
# print(re.findall("ab*","a ab abb abbbbbbbbbbbb bbbbbbbbb"))
# a ab abb abbbbbbbbbbbb bbbbbbbbb
#                        ab*

# 9.4 +: 左边那个字符出现1次或者无穷次
# print(re.findall("ab+","a ab abb abbbbbbbbbbbb bbbbbbbbb"))
# a ab abb abbbbbbbbbbbb bbbbbbbbb
# ab+

# 9.5 {n,m}: 左边那个字符出现n次到m次
# print(re.findall("ab{0,}","a ab abb abbbbbbbbbbbb bbbbbbbbb"))
# print(re.findall("ab*","a ab abb abbbbbbbbbbbb bbbbbbbbb"))
# print(re.findall("ab{1,}","a ab abb abbbbbbbbbbbb bbbbbbbbb"))
# print(re.findall("ab+","a ab abb abbbbbbbbbbbb bbbbbbbbb"))

# print(re.findall("ab{2,5}","a ab abb abbb abbbb abbbbbbbb abbbbbbbbbbbb bbbbbbbbb"))

# 9.6 ?: 左边那个字符出现0次到1次
# print(re.findall("ab?","a ab abb abbbbbbbbbbbb bbbbbbbbb"))


# 9.7 .*: 匹配所有
# print(re.findall("a.*b","123 a1231-==-000b123123123123123b"))
# 123 a1231-==-000b123123123123123b
#     a.*b

# print(re.findall("a.*?b","123 a1231-==-000b123123123123123b"))

# 例1：
msg = ‘<a href="https://pan.baidu.com/s/1skWyTT7" target="_blank"><strong><span style="color: #ff0000;">原理图：https://pan.baidu.com/s/1skWyTT7</span></strong></a><a href="https://www.baidu/com">"点我啊"</a>‘
url_pattern = re.compile(‘href="(.*?)"‘)
# res=url_pattern.findall(msg)
# print(res)

res=url_pattern.findall(‘<a href="www.sina.com.cn"></a>‘)
print(res)

# 例2：
print(re.findall("a.*b","a1b a+b a-b a\nb a\tb",re.DOTALL))

# 10 ():分组
# print(re.findall(‘ab+‘,‘ababab123‘)) #[‘ab‘, ‘ab‘, ‘ab‘]
# print(re.findall(‘(ab)+123‘,‘ababab123‘)) #[‘ab‘]，匹配到末尾的ab123中的ab
# ababab123
# (ab)(ab)(ab)(ab)

# 10.1 取消分组
# print(re.findall(‘(?:ab)+123‘,‘ababab123‘)) #findall的结果不是匹配的全部内容，而是组内的内容,?:可以让结果为匹配的全部内容


# 11 |：或者
# print(re.findall("compan(?:ies|y)","Too many companies have gone bankrupt, and the next one is my company‘"))

# Too many companies have gone bankrupt, and the next one is my company
#                                                               compan(ies|y)

# print(re.findall("\d+\.?\d*","as9fdasl333...4444df1111asdf3333dfadf333.44dafadf3.5555asdfsafd.5555"))
# as9fdasldf1111asdf3333dfadf333.44dafadf3.5555asdfsafd.5555
#                            \d+\.?\d*



# 12. \
# print(re.findall(‘a\\\\c‘,‘a\c a1c aac‘)) #对于正则来说a\\c确实可以匹配到a\c,但是在python解释器读取a\\c时，会发生转义，然后交给re去执行，所以抛出异常
# print(re.findall(r‘a\\c‘,‘a\c a1c aac‘)) #对于正则来说a\\c确实可以匹配到a\c,但是在python解释器读取a\\c时，会发生转义，然后交给re去执行，所以抛出异常

import re

# print(re.findall(‘e‘,‘alex make love‘) )   #[‘e‘, ‘e‘, ‘e‘],返回所有满足匹配条件的结果,放在列表里
# print(re.search(‘e‘,‘alex make love‘)) #e,只到找到第一个匹配然后返回一个包含匹配信息的对象,该对象可以通过调用group()方法得到匹配的字符串,如果字符串没有匹配，则返回None。


# print(re.search("\d+\.?\d*","1.3 aa3.44aaa").group())
# print(re.search("\d+\.?\d*","asdfsadf"))

# print(re.search("\d+\.?\d*"," 1.3 aa3.44aaa"))
# print(re.match("\d+\.?\d*"," 1.3 aa3.44aaa"))

# msg="egon:18-male=10"
# print(msg.split(‘:‘))

# print(re.split(‘[:=-]‘,msg))


# msg=‘<a href="https://pan.baidu.com/s/1skWyTT7" target="_blank"><strong><span style="color: #ff0000;">原理图：https://pan.baidu.com/s/1skWyTT7</span></strong></a><a href="https://www.baidu/com">"点我啊"</a>‘
# print(re.findall(‘href=".*?"‘,msg))