python -beautifulousoup-如何针对n个孩子并打印文字

Question

我正在尝试在

。我在Div class_ ='SC-1RMT1NR-0 SC-1RMT1NR-2 IMYVIY'中访问第n个孩子（最大获益）'

我设法从“趋势”部分获取数据“最大的获利者”前3个文本项目。

我得到attributeError：'nontype'对象没有属性'p'

from bs4 import BeautifulSoup
import requests


source = requests.get('https://coinmarketcap.com/').text

soup = BeautifulSoup(source, 'lxml')

section = soup.find(class_='sc-1rmt1nr-0 sc-1rmt1nr-2 iMyvIy')

#List the top 3 Gainers 
for top_gainers in section.find_all(class_='sc-16r8icm-0 sc-1uagfi2-0 bdEGog sc-1rmt1nr-1 eCWTbV')[1]:
    top_gainers = top_gainers.find(class_='sc-1eb5slv-0 iworPT')
    top_coins = top_gainers.p.text
    print(top_coins)

Answer 1

我会避免使用这些动态的类，而是使用 - ：汤包室和组合者首先通过文本找到所需的块，然后使用组合者指定最终元素的关系以从中提取信息。

import requests
from bs4 import BeautifulSoup as bs
import pandas as pd

soup = bs(requests.get("https://coinmarketcap.com/").text, "lxml")
biggest_gainers = []

for i in soup.select(
    'div[color=text]:has(span:-soup-contains("Biggest Gainers")) > div ~ div'
):
    biggest_gainers.append(
        {
            "rank": int(i.select_one(".rank").text),
            "currency": i.select_one(".alias").text,
            "% change": f"{i.select_one('.icon-Caret-up').next_sibling}",
        }
    )

gainers = pd.DataFrame(biggest_gainers)
gainers

Answer 2

如@qharr所述，您应该避免使用与他的方法相似的动态标识符，而选择通过： - soup-contains（）和该元素的已知文本：

soup.select('div:has(>div>span:-soup-contains("Biggest Gainers")) ~ div')

提取我使用的文本spripped_strings并用键将其划为dict：

dict(zip(['rank','name','alias','change'],e.stripped_strings))

示例

from bs4 import BeautifulSoup
import requests

url = 'https://coinmarketcap.com/'
soup=BeautifulSoup(requests.get(url).content)
data = []
for e in soup.select('div:has(>div>span:-soup-contains("Biggest Gainers")) ~ div'):
    data.append(dict(zip(['rank','name','alias','change'],e.stripped_strings)))

输出

[{'rank': '1', 'name': 'Tenset', 'alias': '10SET', 'change': '1406.99'},
 {'rank': '2', 'name': 'Burn To Earn', 'alias': 'BTE', 'change': '348.89'},
 {'rank': '3', 'name': 'MetaCars', 'alias': 'MTC', 'change': '332.05'}]

Answer 3

您可以使用：type来找到“最大的获利者”父div：

import requests
from bs4 import BeautifulSoup as soup
d = soup(requests.get('https://coinmarketcap.com/').text, 'html.parser')
bg = d.select_one('div:nth-of-type(2).sc-16r8icm-0.sc-1uagfi2-0.bdEGog.sc-1rmt1nr-1.eCWTbV')
data = [{'rank':i.select_one('span.rank').text, 
         'name':i.select_one('p.sc-1eb5slv-0.iworPT').text,
          'change':i.select_one('span.sc-27sy12-0.gLZJFn').text}
        for i in bg.select('div.sc-1rmt1nr-0.sc-1rmt1nr-4.eQRTPY')]

输出：

[{'rank': '1', 'name': 'Tenset', 'change': '1308.72%'}, {'rank': '2', 'name': 'Burn To Earn', 'change': '421.82%'}, {'rank': '3', 'name': 'Aigang', 'change': '329.63%'}]