Question

我刚收到一封带有lxml库的解释Python Web Scraping很好的电子邮件，所以我想测试一下结果。我试图在“有关zip的信息（标题，价格，标签，total_platforms）：”中打印某些内容，但无法在此函数内甚至类型（对象）中打印。 Resp词典不会保存数据，Pycharm中的调试器只是跳过了这一块。我尝试打印输出，但显示为空。有人可以向我解释这种情况吗？

import requests
import lxml.html

html = requests.get('https://store.steampowered.com/explore/new/')
doc = lxml.html.fromstring(html.content)

new_releases = doc.xpath('//div[@id="tab_newreleases_content"]')[0]

titles = new_releases.xpath('.//div[@class="tab_item_name"]/text()')
prices = new_releases.xpath('.//div[@class="discount_final_price"]/text()')

tags = [tag.text_content() for tag in new_releases.xpath('.//div[@class="tab_item_top_tags"]')]
tags = [tag.split(', ') for tag in tags]

platforms_div = new_releases.xpath('.//div[@class="tab_item_details"]')
total_platforms = []

for game in platforms_div:
    temp = game.xpath('.//span[contains(@class, "platform_img")]')
    platforms = [t.get('class').split(' ')[-1] for t in temp]
    if 'hmd_separator' in platforms:
        platforms.remove('hmd_separator')
    total_platforms.append(platforms)
output = []
for info in zip(titles,prices, tags, total_platforms):
    resp = {}
    resp['title'] = info[0]
    resp['price'] = info[1]
    resp['tags'] = info[2]
    resp['platforms'] = info[3]
    output.append(resp)

src：https://medium.freecodecamp.org/an-intro-to-web-scraping-with-lxml-and-python-b02b7a3f3098

Answer 1

这是因为/// <summary> /// T can only be an int or double or will throw an exception on construction. /// </summary> /// <typeparam name="T">Must be int or double.</typeparam> public class A<T> { public A() { if (!(property is int || property is double)) throw new Exception("A can only work with int and double"); } public T property { get; set; } }对象是一个迭代器。
循环迭代器的所有元素时，该对象将为空。因此，您需要将分配替换为zip并使用resp。

print(info)

输出：

for info in zip(titles,prices, tags, total_platforms):
    print(info)

Print（）在zip（）的'for'循环中不起作用

1 个答案: