Question

我要买房子，并且已经建造了BeautifulSoup刮板，它的作用就像一种魅力-从我们当地的房地产网站刮下我需要的标签。现在，我只需要实现一种机制，该机制会在网站发生更改时通知我。

当新的抓取输出与上一个不同（HTML更改时），我需要它通知我。

previous_content = ''
URL = 'whatever.com'

while True:
    content = requests.get(URL)
    soup = BeautifulSoup(content.text, 'html.parser')
    titles = soup.find_all('span', attrs={'class':['title']})
    years = soup.find_all('span', attrs={'class':['year']})
    sizes = soup.find_all('span', attrs={'class':['size']})
    prices = soup.find_all('span', attrs={'class':['price']})

    for titles, years, sizes, prices in zip(titles, years, sizes, prices):
        print('Location: ' + titles.get_text(strip="True") + '\n' + 'Year: ' + years.get_text(strip="True"), '\n' + 'Size: ' + sizes.get_text(strip="True"), '\n' 'Price: ' + prices.get_text(strip="True"))
        previous_content = new_content
    if previous_content == new_content:
        print("CONTENT NOT CHANGED. | " + str(today))
    elif previous_content != new_content:
        print("CONTENT CHANGED | " + str(today))
    time.sleep(sleeptime)

非常感谢！

Answer 1

我认为您在分配previous_content

时犯了一个小错误

您应该在while迭代结束时分配previous_content，而不是在使用new_content测试相等性之前分配它，否则它将始终为True

类似的东西应该起作用（我无法测试）

previous_content = []
URL = 'whatever.com'

while True:
    content = requests.get(URL)
    soup = BeautifulSoup(content.text, 'html.parser')
    titles = soup.find_all('span', attrs={'class':['title']})
    years = soup.find_all('span', attrs={'class':['year']})
    sizes = soup.find_all('span', attrs={'class':['size']})
    prices = soup.find_all('span', attrs={'class':['price']})

    new_content = [] # Initialize the new_content list
    for titles, years, sizes, prices in zip(titles, years, sizes, prices):
        content = 'Location: ' + titles.get_text(strip="True") + '\n' + 'Year: ' + years.get_text(strip="True"), '\n' + 'Size: ' + sizes.get_text(strip="True"), '\n' 'Price: ' + prices.get_text(strip="True")
        print(content)
        new_content.append(content)
    if sorted(previous_content) == sorted(new_content): # The list needs to be sorted as I expect the order to change but not the content
        print("CONTENT NOT CHANGED. | " + str(today))
    else:
        print("CONTENT CHANGED | " + str(today))
    previous_content = new_content # Assigning for next iteration of the loop
    time.sleep(sleeptime)

比较BeautifulSoup结果

1 个答案: