python - Python新手，我做错了什么并且没有看到BS4返回的标签（链接）

Answer 1

您的制表错误...您在 my_spider 函数中调用 my_spider...删除最后一行的制表，它应该可以正常工作。

Answer 2

如果您在实际函数中有函数调用，则您实际上并没有运行该函数，在您更正您将收到错误后，因为这不是传递给请求的有效 url，最后您soup.findAll('a', {'h3 class': "two-lines-name"})将找不到任何东西：

def my_spider(max_pages):
    # use range from 1 to max pages 
    for i in range(1, max_pages+1):
        url = 'http://www.buya.com/Store/SAM-S-LOCKER/400?page={}'.format(i) # http:/?...
        source_code = requests.get(url)
        plain_text = source_code.content
        soup = BeautifulSoup(plain_text)
        # you want the h3 tags and to extract the href from the a tags
        for link in soup.findAll("h3", {'class': "two-lines-name"}):
            href = link.a["href"]
            print(href)


my_spider(5) # outside the function

输出：

/Item/Details/12-FT-CHAIN-W-HOOK/cbb1eb65b100459283d15102606208c2/400
/Item/Details/12-INCH-FUSION-SUBWOOFER/534c4d677b2547fb814668b7d061df5d/400
/Item/Details/18-Gold-Chain-14K-Yellow-Gold-2-03g/0aaf2e1e5532461884cb44e786329e80/400
/Item/Details/1820-HANDMADE-STRAIGHT-RAZOR/ed0ba44f98224067b595b726bf01f5ab/400
/Item/Details/2-PAIRS-OF-POCKET-PLIERS-LEATHERMAN/410bcb9e4321426487bee7639b3cb96e/400
/Item/Details/20TH-CENTURY-FOX-Motorcycle-Helmet-RACING-HELMET/e12a75dc7e004e5aa43698c1edf87773/400
/Item/Details/30-CLUBS/a65f1cbff00c4d59ac998dee96eed98b/400
/Item/Details/30-STEEL-CHAINSAW-BLADE/daaca24ede1341c58bb0d0cd32051646/400
/Item/Details/5-GALLON-GLASS-JUG-BREWING-JUG-CHANGE-JAR/dde9b1bfea2a4a23ad93da098ffc674d/400
/Item/Details/5150-SNOWBOARDS-Snowboard-5150-155CM/bcaa07c71c8c4b499a70d34459244f75/400
/Item/Details/6-FT-STEEL-CHAIN/7c24fb1a16ac46e7b9e91f99883652f6/400
/Item/Details/6-5-CUSTOM-HUNTING-KNIFE/ffda1685b2324abe96e3fb7cb6f7f265/400
/Item/Details/95150/39cb080edd474eb6b770b26b40e3dc6b/400
/Item/Details/ACER-Monitor-P201W/ff03d9c33ca747e08e4646d2c3d5143e/400
/Item/Details/ACOUSTIC-RESEARCH-Monitor-Speakers-RESEARCH-AW825/856ff1d8beb9480d893f94d9d49a8642/400
/Item/Details/ACTIVISION-Microsoft-XBOX-360-CALL-OF-DUTY-BLACK-OPS-2-XBOX-360/aef62055b4f14e379f2eea154d162551/400
/Item/Details/ACTIVISION-Video-Game-Accessory-DJ-HERO-95837809/41e3c7f0114e497caf23d8a50fe1f547/400
/Item/Details/ACTIVISION-Video-Game-Accessory-WII-FIT/7daee2a759a54dd7a4e2b6acd37b9c3e/400
/Item/Details/AIMTECH-1911-SCOPE-MOUNT/ac69ae1c40fe4d7db8c53a8ebf842d7d/400
/Item/Details/AIRCO-TIG-WELDING-TUNGSTEN-Arc-Welder-ELECTRODE/70b9b35db0c547c29eb90e02ef60d91a/400
/Item/Details/AIWA-Portable-CD-Player-XP-SP911/75761bfff9a44093be51e4d70410bd85/400
/Item/Details/ALESSI-Gent-s-Wristwatch-KARIM-RASHID/251c3f95173f49078722b301e1d920fe/400
/Item/Details/ALL-AMERICAN-RIDER-Motorcycle-Part-SADDLE-BAGS/87634c0c08d2458ba5b84fa39c9bc3fc/400
/Item/Details/ALL-AMERICAN-RIDER-Motorcycle-Part-SADDLE-BAGS/803f6dfdc9f44326a5a52b63681779ad/400
/Item/Details/ALLY-SKATEBAORD-USED/716cec1588d9408e859718f5961e1ec6/400
/Item/Details/ALPINE-ARCHERY-Bow-FRONTIER/e73dda8034cf4cdb8ebeeebc9683b55d/400
/Item/Details/AMAZON-Tablet-KINDLE-D01100/ea9ac5b291ef487ea6f75ca328e05750/400
/Item/Details/AMAZON-Tablet-KINDLE-FIRE-D01400/ebe0e7001ac744ffa030fd153942a548/400
/Item/Details/APPLE-Computer-Accessories-A1023/6a38f60d2e034dc597043cc42282246e/400
/Item/Details/APPLE-Cell-Phone-Smart-Phone-IPHONE-5C-A1532-AT-T/cc65c513e848475c8000b6e10b6855e5/400
/Item/Details/APPLE-IPOD-IPOD-A1199-2GB/d1003297dbe7443c8953750f0c96c62a/400
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