day18_ entered Day 18 --re million annual salary of a regular expression

day18

The re module - Regular Expressions

Matching

• findall (): Find all content from a string and returns a list

s = "meet_宝元_meet"
print(re.findall("meet",s))
# ['meet', 'meet']

• \ W: Find numbers, letters (Chinese), underscore
• \ W: Finding non-numeric, alphabetic (Chinese), underscore

s = "meet_宝元_meet123"
print(re.findall("\w",s))
print(re.findall("\W",s))
# ['m', 'e', 'e', 't', '_', '宝', '元', '_', 'm', 'e', 'e', 't', '1', '2', '3']
# []

• \ S: Find any spaces, line breaks, tabs
• \ S: Find a non-arbitrary spaces, line breaks, tabs

s = "meet_ 宝元_ meet123    "
print(re.findall("\s",s))
print(re.findall("\S",s))
# [' ', ' ', ' ', ' ', ' ', ' ']
# ['m', 'e', 'e', 't', '_', '宝', '元', '_', 'm', 'e', 'e', 't', '1', '2', '3']

• \ D: Find figures
• \ D: Finding non-numeric

s = "meet_ 宝元_ 123    "
print(re.findall("\d",s))
print(re.findall("\D",s))
# ['1', '2', '3']
# ['m', 'e', 'e', 't', '_', ' ', '宝', '元', '_', ' ', ' ', ' ', ' ', ' ']

• \ A ^ or: Look for what is beginning to

s = "meet_ 宝元_ 123    "
print(re.findall("\Ameet",s))
print(re.findall("^meet",s))
# ['meet']
# ['meet']

• \ Z or $: end to find out whether what

s = "meet_ 宝元_ 123    tt"
print(re.findall("t\Z",s))
print(re.findall("tt$",s))
# ['t']
# ['tt']

• \ N: Find newline

s = "meet宝元_123meet \n \t \n"
print(re.findall("\n",s))
# ['\n', '\n']

• \ T: Find Tabs

s = "meet宝元_123meet \n \t \n"
print(re.findall("\t", s))
# ['\t']

• : Only match any of the contents (non-newline)

s = "m\net宝元_123maet \n \t "
print(re.findall("m.e", s))
print(re.findall("m.e", s,re.DOTALL))
# ['mae']
# ['m\ne', 'mae']

• []: Matching characters in a character set

s = "meet宝元_1A-23maet"
print(re.findall("[a-z]", s))  # 小写的a-z
print(re.findall("[A-Z]", s))  # 大写的A-Z
print(re.findall("[a-zA-Z]", s))  # 大小写的20字母
print(re.findall("[a-zA-Z0-9]", s))  # 大小写的20字母,0-9
print(re.findall("[^0-9]", s))  # 查找非0-9的内容
# ['m', 'e', 'e', 't', 'm', 'a', 'e', 't']
# ['A']
# ['m', 'e', 'e', 't', 'A', 'm', 'a', 'e', 't']
# ['m', 'e', 'e', 't', '1', 'A', '2', '3', 'm', 'a', 'e', 't']
# ['m', 'e', 'e', 't', '宝', '元', '_', 'A', '-', 'm', 'a', 'e', 't']

• *: 0 or more matches [greedy matches]

s = "m mm mmmmmm"
print(re.findall("m*", s))
print(re.findall("m*m", s))
# ['m', '', 'mm', '', 'mmmmmm', '']
# ['m', 'mm', 'mmmmmm']

• +: 1 or more Match [greedy matches]

s = "m mm mmmmmm"
print(re.findall("m+", s))
print(re.findall("m+m", s))
# ['m', 'mm', 'mmmmmm']
# ['mm', 'mmmmmm']

• ?: Matches zero or one [non-greedy matches]

s = "m mm mmmmmm"
print(re.findall("m?",s))
# ['m', '', 'm', 'm', '', 'm', 'm', 'm', 'm', 'm', 'm', '']

• SUMMARY {n}: Find what repeated n times

s = "m mm mmm mmmm mmmmm mmmmmm"
print(re.findall("m{2}", s))
print(re.findall("m{4}", s))
print(re.findall("m{6}", s))
# ['mm', 'mm', 'mm', 'mm', 'mm', 'mm', 'mm', 'mm', 'mm']
# ['mmmm', 'mmmm', 'mmmm']
# ['mmmmmm']

• SUMMARY {n, m}: Find what times repeated nm

s = "m mm mmm mmmm mmmmm mmmmmm"
print(re.findall("m{2,5}", s))
# ['mm', 'mmm', 'mmmm', 'mmmmm', 'mmmmm']

• a | b: or

s = "m mm mmss ss s"
print(re.findall("m|s", s))
# ['m', 'm', 'm', 'm', 'm', 's', 's', 's', 's', 's']

• (): Matching expression in brackets, also represents a group

s = "meet_assdf_mssst_(.)mmns_aaamaaatmsssssssssssstt"
print(re.findall("m(..)t", s))
print(re.findall("m(.?)t", s))
print(re.findall("m(..?)t", s))
print(re.findall("m(?:..?)t",s))  # ?:m和t都连上
print(re.findall("m(.*)t", s))
print(re.findall("m(.*?)t", s))
print(re.findall("m(.+)t", s))
print(re.findall("m(.+?)t", s))
# ['ee']
# []
# ['ee']
# ['meet']
# ['eet_assdf_mssst_(.)mmns_aaamaaatmsssssssssssst']
# ['ee', 'sss', 'mns_aaamaaa', 'ssssssssssss']
# ['eet_assdf_mssst_(.)mmns_aaamaaatmsssssssssssst']
# ['ee', 'sss', 'mns_aaamaaa', 'ssssssssssss']

print(re.search("(?P<tag_name>\w+)\w+\w+","h1hellh1").group())
print(re.search("(?P<aaa>\w+)dfa","asbsadfasdfa").group("aaa"))
print(re.search("(?P<cx>\w+)dfa","asbsadfasdfa").group())
# h1hellh1
# asbsadfas   # ?P：命名
# asbsadfasdfa

s = 'alex_sb ale123_sb wu12sir_sb wusir_sb ritian_sb 的 alex wusir '
print(re.findall("\w+_sb",s))
print(re.findall("[a-z]+_sb",s))
# ['alex_sb', 'ale123_sb', 'wu12sir_sb', 'wusir_sb', 'ritian_sb']
# ['alex_sb', 'sir_sb', 'wusir_sb', 'ritian_sb']

method

• search (): find a stop after the search, to find the string, after finding an object is returned, view the elements (group ())

s = '_sb alex 123_sb wu12sir_sb wusir_sb ritian_sb 的 x wusir '
print(re.search("ale",s)) # 如果不存在返回None
print(re.search("ale",s).group()) # 如果不存在报错
# <re.Match object; span=(4, 7), match='ale'>
# ale

• match (): stop the search after finding a look only from the beginning of the string, returns an object after find, view elements (group ())

s = 'ale_sb alex 123_sb wu12sir_sb wusir_sb ritian_sb 的 x wusir '
print(re.match("ale",s))  # 开头找不到就返回None
print(re.match("ale",s).group()) # 开头找不到就报错
# <re.Match object; span=(0, 3), match='ale'>
# ale

• split (): split

s = '_sb alex,123:sb;wu12sir#sb*wusir!sb ritian_sb 的 x wusir '
print(re.split("[#,:!*]",s))
# ['_sb alex', '123', 'sb;wu12sir', 'sb', 'wusir', 'sb ritian_sb 的 x wusir ']

• sub (): Replace

print(re.sub("barry","宝元",'barry是最好的讲师，barry就是一个普通老师，请不要将barry当男神对待。'))
# 宝元是最好的讲师，宝元就是一个普通老师，请不要将宝元当男神对待。

• compile (): defined matching rules

obj = re.compile("\w")
print(obj.findall("meet_宝元_阿萨大大"))
print(re.findall("\w","meet_宝元_阿萨大大"))
# ['m', 'e', 'e', 't', '_', '宝', '元', '_', '阿', '萨', '大', '大']
# ['m', 'e', 'e', 't', '_', '宝', '元', '_', '阿', '萨', '大', '大']

• finditer (): Returns an iterator address

g = re.finditer("\w","大大撒旦")
# print(next(g).group())
for i in g:
    print(i.group())
# 大
# 大
# 撒
# 旦

Exercise

1、取整数
s = "1-2*(60+(-40.35/5)-(-4*3))"
print(re.findall("\d+",s))
# ['1', '2', '60', '40', '35', '5', '4', '3']

1.2 匹配所有的数字（包含小数）
s = "1-2*(60+(-40.35/5)-(-4*3))"
print(re.findall("\d+\.\d+|\d+",s))
# ['1', '2', '60', '40.35', '5', '4', '3']

匹配所有的数字（包含小数包含负号）
s = "1-2*(60+(-40.35/5)-(-4*3))"
print(re.findall("-?\d+\.\d+|-?\d+",s))
# ['1', '-2', '60', '-40.35', '5', '-4', '3']

2,匹配一段你文本中的每行的邮箱
http://blog.csdn.net/make164492212/article/details/51656638 匹配所有邮箱
s = "http://blog.csdn.net/make164492212/article/details/51656638 匹配所有邮箱"
print(re.findall("h(?:.+)ls/", s))
# ['http://blog.csdn.net/make164492212/article/details/']

3，匹配一段你文本中的每行的时间字符串 这样的形式：'1995-04-27'
s1 = '''
时间就是1995-04-27,2005-04-27
1999-04-27 老男孩教育创始人
老男孩老师 alex 1980-04-27:1980-04-27
2018-12-08
'''
print(re.findall("\d+-\d+-\d+",s1))
# ['1995-04-27', '2005-04-27', '1999-04-27', '1980-04-27', '1980-04-27', '2018-12-08']

4、匹配qq号：腾讯从10000开始：
num = input("请输入你的数字：")
print(re.findall("[1-9][0-9]{5,10}",num))
# 请输入你的数字：1719932187171993218
# ['1719932187', '171993218']

s1 = '''
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</div>
'''
1,找到所有的span标签的内容
ret = re.findall('<span(.*?)>', s1)
print(ret)

print(re.findall('<a href="(.*?)"',s1))