Python Regular Expressions

 

 Code

# ! /Usr/bin/ENV Python
# Coding = UTF-8
Import Re
Str = R ' <Docitem key = "founded_place"> <! [CDATA [Guangdong, Shenzhen, China]> </docitem> '
R = Re. Compile (R ' <Docitem key = "(. *)"> (. *) </docitem> ' )
M = R. Match (STR)

PrintM. group (0)
PrintM. Group (1)
PrintM. Group (2)

Print '========================================================== ==='

Str2=M. Group (2)
Str2=Str
PrintStr2
R2=Re. Compile (R". * <! \ [CDATA \ [(. *?)]>")
M2=R2.match (str2)
PrintM2.group (1)

 

<Docitem key = "founded_place"> <! [CDATA [Guangdong, Shenzhen, China]> </docitem>

Founded_place <! [CDATA [Guangdong, Shenzhen, China] >==================================== =============< docitem key = "founded_place"> <! [CDATA [China Guangdong Shenzhen]> </docitem> China Guangdong Shenzhen

 

This is different from the Perl regular expression. In Perl, the mode string is(R"<! [CDATA [(. *?)]>"), But in Python, ". *" must be added before it can be used normally, and "[" must be added with backslash escape. The formula is as follows:

(R". * <! \ [CDATA \ [(. *?)]>")

 

 

II

Another problem is that python does not handle the encoding problem very well. In many cases, the encoding mode needs to be changed for different characters.

#! /Usr/bin/ENV Python

# Coding = UTF-8

Import sys

Reload (sys)

SYS. setdefaultencoding ('gbk ')

Import re

 

Pchinese = Re. Compile (UR '([\ u4e00-\ u9fa5] +) +? ', Re. U)

S = u'2017 test with string 67890,45 this is another 44 Ha'

M = pchinese. findall (s)

If M:

Print ('|'. Join (m ))

Else:

Print ('no found! ')

 

 

3.

#! /Usr/bin/ENV Python

# Coding = UTF-8

#! /Usr/bin/ENV Python

# Coding = UTF-8

Import re

Import sys

Reload (sys)

SYS. setdefaultencoding ('gbk ')

Str1 = R' <docitem key = "founded_place"> <! [CDATA [Guangdong, Shenzhen, China]> </docitem>'

# Str1 = r "CDATA [Guangdong and Shenzhen, China]"

# Str1 = Unicode (str1, 'utf8 ')

Print type (str1)

Re2 = r ". * CDATA \[(.*?) \]"

# Re2 = Unicode (re2, 'utf8 ')

# Print type (re2)

R = Re. Compile (re2) # [\ u4e00-\ u9fa5]

M = R. Match (str1)

Print M. group (0)

Print M. Group (1)