使用scrapy 爬取京东商品名及价格，但是使用CSS并extract() 读不出text.用过scrapy shell 也读出不商品名（我完全是复制的Selector也不行）一直return []

#Create the Spider class

class DC_Description_Spider(scrapy.Spider):

  name = "dc_chapter_spider"

  # start_requests method

  def start_requests(self):

    url_short='https://beauty.jd.com/'

    yield scrapy.Request(url = url_short, callback = self.parse_front)

  # First parsing method

  def parse_front(self, response):

    parent_node = response.css('#app > div > div.lc-floor.lc-xfloor--id-1574665740220.lc-floor--lg > div > div:nth-child(9) > div > div > div.lc-nav-tabs__body > div:nth-child(2) > div > div > div')

    item_dict=[]

    for i in range(4):

        item_name = parent_node.css('>div:nth-child({i}) > div > div.goods-item__info > div.goods-item__title.goods-item__title--twoline').extract()

        item_price=parent_node.css('>div:nth-child({i}) > div > div.goods-item__info > div.goods-item__content > div').extract()

        if item_price == []:

          item_price="补货中"

          item_dict.append({"name":item_name, "price":item_price})

        else:

          item_dict.append({"name":item_name, "price":item_price})

    return item_dict

    #for url in links_to_follow:

      #yield response.follow(url = url,

    #                        callback = self.parse_pages)

 #Run the spider

process = CrawlerProcess()

process.crawl(DC_Description_Spider)

process.start()

# Print a preview of courses

#previewCourses(dc_dict)

有可能是动态网站的原因。