Question

I need to sample and extract only a specific string out of an offline HTML document and write that information nice and clean into a *.txt file.

So for example, lets assume that this is a section of the HTML file:

    <span id="dataView01">001.00 SPL</span>
    <span id="dataView02">543.00 SPL</span>
    <span id="dataView03">056.00 SPL</span>
    <span id="dataView04">228.00 SPL</span>

I need to get this as a result:

   001.00 SPL
   543.00 SPL
   056.00 SPL
   228.00 SPL

Could you please help me with this,
Thanks.

Answer 1

Use an HTML parser like BeautifulSoup.
Example:

from bs4 import BeautifulSoup as bs
import re

markup = '''<span id="dataView01">001.00 SPL</span>
    <span id="dataView02">543.00 SPL</span>
    <span id="dataView03">056.00 SPL</span>
    <span id="dataView04">228.00 SPL</span>'''

soup = bs(markup)
tags = soup.find_all('span', id=re.compile(r'[dataView]\d+'))
for t in tags:  
    print(t.text)

Result:

001.00 SPL
543.00 SPL
056.00 SPL
228.00 SPL

---

Next step; write to .txt file:

import csv

with open('output.txt','wb') as fou:
    csv_writer = csv.writer(fou)
    for tag in tags:
        split_on_whitespace = t.text.split()
        csv_writer.writerow(split_on_whitespace)