如果字符串包含来自列表

Question

我想检查是否有任何被排除的网站出现。我可以让它只在一个站点上工作，但是一旦我把它列在列表中，它就会在if donts in thingy 出错：

TypeError: 'in' 需要字符串作为左操作数，而不是元组"

这是我的代码：

import requests 
from bs4 import BeautifulSoup
from lxml import html, etree
import sys
import re

url = ("http://stackoverflow.com")

donts = ('stackoverflow.com', 'stackexchange.com')

r = requests.get(url, timeout=6, verify=True)

soup = BeautifulSoup(r.content, 'html.parser')

for link in soup.select('a[href*="http"]'):

    thingy = (link.get('href'))

    thingy = str(thingy)

    if donts in thingy:

        pass

    else:

        print (thingy)

Answer 1

import requests 

from bs4 import BeautifulSoup

from lxml import html, etree

import sys

import re

url = ("http://stackoverflow.com")

donts = ('stackoverflow.com', 'stackexchange.com')

r = requests.get(url, timeout=6, verify=True)

soup = BeautifulSoup(r.content, 'html.parser')

for link in soup.select('a[href*="http"]'):

    thingy = (link.get('href'))

    thingy = str(thingy)

    if thingy in donts :

        print (thingy)

    else:

        pass

判断：元组中的字符串

Answer 2

问题的症结在于您如何搜索排除列表：

excluded = ("a", "b", "c")
links = ["a", "d", "e"]

for site in links:
    if site not in excluded:  # We want to know if the site is in the excluded list
        print(f"Site not excluded: {site}")

颠倒你的元素的顺序，这应该可以正常工作。我在这里颠倒了你的逻辑，所以你可以跳过不必要的pass。

作为旁注，这是清晰的变量名称可以提供帮助的原因之一 - 它们将帮助您推理逻辑应该做什么。特别是在存在in 等人体工程学的Python 中，这非常有用。

Answer 3

import requests 

from bs4 import BeautifulSoup

from lxml import html, etree

import sys

import re

url = ("http://stackoverflow.com")

donts = ('stackoverflow.com', 'stackexchange.com')

r = requests.get(url, timeout=6, verify=True)

soup = BeautifulSoup(r.content, 'html.parser')

for link in soup.select('a[href*="http"]'):

    thingy = (link.get('href'))

    thingy = str(thingy)

    if any(d in thingy for d in donts):

        pass

    else:

        print (thingy)