Python uses regular expression text substitution

Three-way client programming in a sense is the material organization, so, the picture material organization often need batch processing, Python must be the best choice, but Win/linux/mac have a simple running environment

Two application scenarios:

• If it is not in a folder, insert the folder name in the previous
• Add a prefix to all filename names

Just look at the code.

# Encoding:utf-8import re# compiles the regular expression into the pattern object P = Re.compile (R ' (? P<folder> (\w+/) *) (? p<filename>\w+\.png) ' # matches the text using pattern, gets the match result, cannot match when will return None#match = Pattern.match (' <key>xxx/ Duobaojiemian_l/yangpizi.png</key> ') The_str = "" "<key>xxxx/duobaojiemian2222_l/duobaojiemian_l/ yangpizi.png</key>    <key>yangpizi2.png</key> <key>yangpizi3.png</key> "" "    For M in P.finditer (THE_STR):  # Use Match to get Group Info  print m.groupdict () print '-------------------------------' #f = Lambda M:m.group (). Find (' xxxx/') = =-1 and ' xxxx/' +m.group () or M.group () def f (m):  s = m.group ()  return S.find (' xxxx/') = =-1 and ' xxxx/' +s or sdef f2 (m2):  d = m2.groupdict ()  return d[' folder ']+ ' the_ ' +d[' filename ']print p.sub (F2, THE_STR)

　　

There are several questions about regular expressions that need to be accounted for.

• Python Regular Expressions Use this syntax if the capture requires grouping (? p< naming > matching regular expressions)
• Re.compile used to compile a regular expression and return an object
• P.finditer return all matching iterators
• P.sub passes the match to the callback function and replaces the text with the return value
• M.groupdict, you can use the group name to take the corresponding value

Python uses regular expression text substitution