Web scraping 特定单词和前后单词数的网页抓取

我在一个段落中寻找一个特定的词“风险”。有人能帮我编码，检查段落中是否有这个词，如果有，我只想在关键词前后提取6个词。提前感谢。

这里有一个简单的例子。但是请注意，如果关键字前后少于6个单词，我没有说明情况。但这给了你一个大致的开始/想法

import bs4 as bs
import urllib.request
import re

sauce = urllib.request.urlopen('url').read()
soup = bs.BeautifulSoup(sauce, 'lxml')

print (soup.text)

test  = soup.findAll (text = re.compile('risk'))
print (test)

输出：

from bs4 import BeautifulSoup
import requests
import re

key_word = 'risk'
url = 'https://www.investing.com/analysis/2-reasons-merck-200373488'

with requests.Session() as s: 
    s.headers = {
        "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.110 Safari/537.36",
        "Accept-Encoding": "gzip, deflate",
        "Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8",
        "Accept-Language": "en"
    } 


response = s.get(url)
soup = BeautifulSoup(response.text,"html.parser")

paragraphs  = soup.findAll(text = re.compile(key_word)) 

if len(paragraphs) == 0:
    print ('"%s" not found.' %(key_word))

else:
    for paragraph in paragraphs:
        #print (paragraph.strip())
        alpha = paragraph.strip().split(' ')

        try:
            idx = alpha.index(key_word)

            six_words = alpha[idx-6: idx] + alpha[idx: idx+7]
            print (' '.join(six_words) + '\n')
        except:
            continue

---

我认为这个解决方案应该有效。如果字符串中的前/后单词少于6个，这也会为您提供一个输出。此外，它与“风险”匹配正确，不会与“风险”之类的内容匹配

您必须进行一些修改以匹配您的用例

cryptocurrencies involves high risks including the risk of losing some, or all, of

investment objectives, level of experience, and risk appetite, and seek professional advice where

---

你有url吗？我只是想帮助你在任何url中使用任何关键字的通用代码。谢谢

from bs4 import BeautifulSoup
import urllib.request
import re
url='https://www.investing.com/analysis/2-reasons-merck-200373488'
req = urllib.request.Request(
    url,
    data=None,
    headers={
'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_9_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.1916.47 Safari/537.36'
    }
)
sauce = urllib.request.urlopen(req).read()
soup=BeautifulSoup(sauce,'html.parser')
pattern=re.compile(r'risk[\.| ]',re.IGNORECASE)#'Risk', 'risk.', 'risk'  but NOT 'risky'
no_of_words=6
for elem in soup(text=pattern):
    str=elem.parent.text
    list=str.split(' ')
    list_indices=[i for i,x in enumerate(list) if re.match(pattern,x.strip()+' ')]# +' ' to conform with our pattern
    for index in list_indices:
        start=index-no_of_words
        end=index+no_of_words+1
        if start<0:
            start=0
        print(' '.join(list[start:end]).strip()) #end will not affect o/p if > len(list)
        print("List of Word Before: ",list[start:index])# words before
        print("List of Words After: ",list[index+1:end])#word after
        print()

Risk Warning
List of Word Before:  []
List of Words After:  ['Warning']

Risk Disclosure:
List of Word Before:  []
List of Words After:  ['Disclosure:']

Risk Disclosure: Trading in financial instruments and/or
List of Word Before:  []
List of Words After:  ['Disclosure:', 'Trading', 'in', 'financial', 'instruments', 'and/or']

cryptocurrencies involves high risks including the risk of losing some, or all, of
List of Word Before:  ['cryptocurrencies', 'involves', 'high', 'risks', 'including', 'the']
List of Words After:  ['of', 'losing', 'some,', 'or', 'all,', 'of']

investment objectives, level of experience, and risk appetite, and seek professional advice where
List of Word Before:  ['investment', 'objectives,', 'level', 'of', 'experience,', 'and']
List of Words After:  ['appetite,', 'and', 'seek', 'professional', 'advice', 'where']

investment objectives, level of experience, and risk appetite, and seek professional advice where
List of Word Before:  ['investment', 'objectives,', 'level', 'of', 'experience,', 'and']
List of Words After:  ['appetite,', 'and', 'seek', 'professional', 'advice', 'where']