re模块2

# 元字符+，*遇到？后就会变为贪婪匹配
print(re.findall('abc+?','abcccccc'))  #['abc']
print(re.findall('abc*?','abcccccc'))  #['ab']
print(re.findall('abc{1,4}','abcccabc')) #['abccc', 'abc']
print(re.findall('abc{1,4}?','abcccabc')) #['abcc', 'abc']
#---------------------------------------------------------------------
#元字符之字符集［］  在字符集里面有功能的字符  - ^ \
print(re.findall("[abc]","sdfgbahjkkk"))
#若是字符集的前后没有字母，就会分别匹配a,b,c ['b', 'a'],否在就字符集里选择一个字母和外面的连接使用
print(re.findall("a[a-z]","fwefaefewaasfwe")) #['ae', 'aa']
print(re.findall("a[.*+]","a.b*c+")) #在字符集里的符号就是普通符号  ['a.']

print(re.findall("[^ab]","fgddab"))  #['f', 'g', 'd', 'd']
print(re.findall("[1-9]","vsd1fdv2sdvsd23")) #['1', '2', '2', '3']
print(re.findall("d[1-9]","vsd1fdv2sdvsd23")) #['d1', 'd2']
print(re.findall("[\d]","af1fsdf2ffsf1")) #['1', '2', '1']
print(re.findall("[1-9]","af1fsdf2ffsf1")) #['1', '2', '1']

print(re.findall("[^\W1-9a-z]","f我1e@f们21在ew2一%&e起1f"))  #['我', '们', '在', '一', '起']
#^\W 就是去掉符号 再去掉数字和字母

#转义字符 \
#反斜杠后面跟元字符会失去特殊功能 如\*
print(re.findall("\*","vdv*vdd"))
print(re.findall("\.","vdf.v*vdd"))
print(re.findall("\?","vd?f.v*vdd"))
print(re.findall("\^","vdf.v*vd^d"))
print(re.findall("\[ab]","vdf.v*v[ab]dd"))
print(re.findall("\{2,3}","vdf.v*v{2,3}dd"))
print(re.findall("\$","vdf.v*v$dd"))
print(re.findall("\+","vdf.v+*vdd"))

反斜杠后边跟元字符去除特殊功能,比如\.
反斜杠后边跟普通字符实现特殊功能,比如\d

\d  匹配任何十进制数；它相当于类 [0-9]。
\D 匹配任何非数字字符；它相当于类 [^0-9]。
\s  匹配任何空白字符；它相当于类 [ \t\n\r\f\v]。
\S 匹配任何非空白字符；它相当于类 [^ \t\n\r\f\v]。
\w 匹配任何字母数字字符；它相当于类 [a-zA-Z0-9_]。
\W 匹配任何非字母数字字符；它相当于类 [^a-zA-Z0-9_]
\b  匹配一个特殊字符边界，比如空格 ，&，＃等

#反斜杠后面跟普通字母可以实现特殊功能 如\d  \w  \s \b
print(re.findall("\d","12f345fs56dsfs"))  #只匹配数字
print(re.findall("[1-9]","12f345fs56dsfs"))
print(re.findall("[^\D]","12f345fs56dsfs"))
print(re.findall("[^a-z]","12f345fs56dsfs"))
#---------------------------------------------------------------------
print(re.findall("\D","12f345fs56dsfs"))  #只匹配字母
print(re.findall("[a-z]","12f345fs56dsfs"))
print(re.findall("[^1-9]","12f345fs56dsfs"))
print(re.findall("[^\d]","12f345fs56dsfs"))

print(re.findall("\w","12f345fs56dsfs")) #匹配所有的字母和数字
print(re.findall("[^\W]","12f345fs.,56dsfs"))
print(re.findall("[1-9a-z]","12f345fs56dsfs"))
#---------------------------------------------------------------------
print(re.findall("\W","12f345f;'s56dsfs")) #匹配符号
print(re.findall("[^\w]","12f345fs,/56dsfs"))
print(re.findall("[^1-9a-z]","12f345fs,/56dsfs"))

#s 匹配空格
print(re.findall("[\s]","a bcd")) #[' ']
print(re.findall("[^\s]","abcd")) #['a', 'b', 'c', 'd']
print(re.findall("\S","abc d"))  #['a', 'b', 'c', 'd']

print(re.findall("[^\s]","ff fse "))  #除了空格 ['f', 'f', 'f', 's', 'e']
print(re.findall("v\\\\h","sdv\hyu"))  #匹配斜杠 ['v\\h']
print(re.findall(r"v\\h","sdv\hyu"))   #匹配斜杠 ['v\\h']
# \b表示匹配一个特殊字符边界
print(re.findall(r"ber\b","sfsber\hj"))  #匹配\b  ber
print(re.findall(r"\bber","sfs:berhj"))  #匹配\b  ber