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  • 爬虫学习路径

    1

    import requests
    url = "https://item.jd.com/2967929.html"
    try:
        r = requests.get(url)
        r.raise_for_status()   ##
        r.encoding = r.apparent_encoding
        print(r.text[:1000])
    except:
        print("爬取出错")
    
    

    ip地址查询

    url = "http://m.ip138.com/ip.asp?ip="
    try:
        r = requests.get(url + "202.204.80.112")
        r.raise_for_status()   ##
        r.encoding = r.apparent_encoding
        print(r.text[-500:])  ##防止文本过大导致卡机
    except:
        print("爬取失败")
    
    

    beautifulsoup

    from bs4  import BeautifulSoup
    import requests
    r = requests.get("http://python123.io/ws/demo.html")
    r.text
    demo = r.text
    soup = BeautifulSoup(demo, "html.parser")
    #soup = BeautifulSoup(open("d://demo.html"), "html.parser")
    
    print(soup.prettify())  ##格式化打印
    
    

    基本元素

    标签使用

    soup.a.name 
    tag = soup.a
    tag.attrs
    tag.attrs['class']
    tag.attrs['href']
    
    



    标签树上行遍历

    for  parent in soup.a.parents:
        if parent is None:
            print(parent)
        else: 
            print(parent.name)
    
    



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  • 原文地址:https://www.cnblogs.com/g2thend/p/12285118.html
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