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Python 不确定如何使用XPath访问特定的网站元素_Python_Css_Python 2.7_Xpath_Scrapy - Fatal编程技术网

Python 不确定如何使用XPath访问特定的网站元素

Python 不确定如何使用XPath访问特定的网站元素,python,css,python-2.7,xpath,scrapy,Python,Css,Python 2.7,Xpath,Scrapy,我目前正在尝试使用Scrapy来浏览Elite危险的subreddit,收集帖子标题、URL和投票计数。前两个我做得很好,但不确定如何编写XPath表达式来访问投票 selector.xpath('//div[@class=“score unnoted”]').extract()可以工作,但它会返回当前页面上所有帖子(而不是每个帖子)的投票计数response.css('div.score.unnoted').extract()适用于每个帖子,但返回[u'1'],而不是仅返回1。(我还想知道如何

我目前正在尝试使用Scrapy来浏览Elite危险的subreddit,收集帖子标题、URL和投票计数。前两个我做得很好,但不确定如何编写XPath表达式来访问投票

selector.xpath('//div[@class=“score unnoted”]').extract()可以工作,但它会返回当前页面上所有帖子(而不是每个帖子)的投票计数
response.css('div.score.unnoted').extract()
适用于每个帖子,但返回
[u'1']
,而不是仅返回1。(我还想知道如何使用XPath做到这一点!:)

代码如下:

class redditSpider(CrawlSpider):  # http://doc.scrapy.org/en/1.0/topics/spiders.html#scrapy.spiders.CrawlSpider
    name = "reddits"
    allowed_domains = ["reddit.com"]
    start_urls = [
    "https://www.reddit.com/r/elitedangerous",
    ]

    rules = [
        Rule(LinkExtractor(
            allow=['/r/EliteDangerous/\?count=\d*&after=\w*']),  # Looks for next page with RE
        callback='parse_item',  # What do I do with this? --- pass to self.parse_item
        follow=True),  # Tells spider to continue after callback
    ]

    def parse_item(self, response):
        selector_list = response.css('div.thing') # Each individual little "box" with content

        for selector in selector_list:
            item = RedditItem()
            item['title'] = selector.xpath('div/p/a/text()').extract()
            item['url'] = selector.xpath('a/@href').extract()
            # item['votes'] = selector.xpath('//div[@class="score unvoted"]')
            item['votes'] = selector.css('div.score.unvoted').extract()
            yield item

你在正确的轨道上。第一种方法只需要两件事:

  • 开始时的一个点使其
  • text()
    结尾处
固定版本:

selector.xpath('.//div[@class="score unvoted"]/text()').extract()
并且,仅供参考,您也可以使用以下方法使第二个选项起作用:

这应该行得通-

selector.xpath('//div[contains(@class, "score unvoted")]/text()').extract()

谢谢,特定于上下文的点使一切变得更容易:)。再次感谢::text pseudo-element.Same问题,它返回整个页面的投票,而不仅仅是当前div.selector.xpath(“//div[contains(@class,“score unnoted”))]/text()”[0]。extract()
selector.xpath('//div[contains(@class, "score unvoted")]/text()').extract()