Changing A Path Class Name In Svg Python

This question is a direct follow up to the question right here: String manipulation when given an integer parameter Python I'll explan. I have this SVG image (just an example): <

Solution 1:

Use LXML python module to parse the SVG file. Then you can access all of the nodes and attributes quickly and easily. I do this all the time for XML, HTML, and SVG. Brute force string parsing is almost never the right way to go especially when dealing with a well formed language syntax like XML, SVG, and CSS.

I'm typing on my phone so I can't provide you with any examples right now. However, rest assured that LXML is simple to use and gives you a robust solution; robust unlike any string parsing code that you hack together.

Using XPath, you can easily find all of the nodes and modify their attributes. In your case:

for node in doc.xpath ("//path"):
    node.get ("class")

Solution 2:

There is probably a parser doing the job, but by using open and re.sub, you can do:

import re
defincrement_value_in_string (s, inc_value):
    return re.sub('(?<=cls-)\d*',lambda m: str(inc_value+int(m.group(0))),s)
# note: '(?<=cls-)\d*' is slightly different than in my answer to your previous # question as the pattern is less restrictive# open your svg file and read
svg_file = open('path_to_your_file\file.svg','r')
svg_txt = svg_file.read()

# increment the value after cls- by 5
increment_value = 5
svg_txt_modif = increment_value_in_string (svg_txt, increment_value)

# write back to a svg file
file_modif_svg = open('path_to_your_file\file_modif.svg','wb')
file_modif_svg.write(svg_txt_modif)
file_modif_svg.close()

The file file_modif.svg has the value incremented by 5 everytime digits are after the pattern 'cls-'