Question

我正在做以下Nokogiri教程：http://hunterpowers.com/data-scraping-and-more-with-ruby-nokogiri-sinatra-and-heroku/

所以我试图在终端中启动这个脚本：

require 'nokogiri'
require 'open-uri'

url = "http://www.930.com/concerts/#/930/"

data = Nokogiri::HTML(open(url))

# Here is where we use the new method to create an object that holds all the
# concert listings.  Think of it as an array that we can loop through.  It's
# not an array, but it does respond very similarly.
concerts = data.css('.concert_listing')

concerts.each do |concert|
  # name of the show
  puts concert.at_css('.event').text

  # date of the show
  puts concert.at_css('.date').text

  # time of the show
  puts concert.at_css('.doors').text

  # show price or sold out
  # Remember, when a show is sold out, there is no div with the selector .price
  # What we are doing here is setting price = to that selector.  We then test
  # to see whether it is nil or not which let's us know if the show is SOLD OUT.
  price = concert.at_css('.price')
  if !price.nil?
    puts price.text
  else
    puts "SOLD OUT"
  end

  # blank line to make results prettier
  puts ""

end

$ ruby interesting.rb

但没有任何反应：

alex @ alex-K43U：〜/ rails / nokogiri $ ruby interesting.rb

亚历克斯@亚历克斯-K43U：〜/轨道/引入nokogiri $

我过去常常使用Rails做所有事情，所以现在从一个空文件夹开始对我来说似乎有点混乱。

如何在此文件夹中安装gem，如何正确启动脚本？

Answer 1

对我来说很正常！你确定这一行：

concerts = data.css('.concert_listing')

会导致concerts中有任何可枚举的内容吗？你有没有尝试过它？

puts concerts

Answer 2

如果您访问该站点，并弹出浏览器控制台并检查该页面，您将看到他们更改了音乐会的css类，因此它不再是.concert_listing。
分析网站，看看你可以获取什么，以及如何使用Nokogiri获取它。

使用gem依赖项启动ruby脚本但根本没有框架？

2 个答案: