如何使用Nokogiri解析维基百科中嵌套很深的文本

Question

我正试图从http://en.wikipedia.org/wiki/List_of_current_NBA_team_rosters

这是我的新手代码位：

class AllPlayersScraper
  attr_accessor :players, :names, :links
  def initialize(url)
    @players = Nokogiri::HTML(open(url))
  end
  def get_names
    @names = @players.css('table[class^="sortable"]')
    # @names = @players.css("div.span2 a").href
  end
end

require_relative './config/environment.rb'
rawfeed = "http://en.wikipedia.org/wiki/List_of_current_NBA_team_rosters"
scraper = AllPlayersScraper.new(rawfeed)
nbalist = scraper.get_names

这是我遇到麻烦的HTML块。我不知道如何钻取我需要的第三个<td>。

<table class="sortable jquery-tablesorter" style=....>
<thead> 
   // bunch of html...
</thead>
<tbody>
    <tr>
    <td style="text-align:center;"><span style="display:none" class="sortkey">5.5 !</span><span class="sorttext"><a href="/wiki/Forward-center" title="Forward-center">F/C</a></span></td>
    <td style="text-align:center;">50</td>
    <td style="text-align:left;"><a href="/wiki/Lavoy_Allen" title="Lavoy Allen">Allen, Lavoy</a></td>
    <td><span style="display:none" class="sortkey">81 !</span><span class="sorttext">6 ft 9 in</span> (2.06&#160;m)</td>
    <td>255 lb (116&#160;kg)</td>
    <td style="text-align:center;">1989–02–04</td>
    <td><a href="/wiki/Temple_University" title="Temple University">Temple</a></td>
    </tr>

谢谢！

Answer 1

长时间不使用Nokogiri，但这很有效：

rawfeed = "http://en.wikipedia.org/wiki/List_of_current_NBA_team_rosters"
@page = Nokogiri::HTML(open(rawfeed))
@all_teams = @page.css('table.toccolours')
@parsed_teams = []
@all_teams.each do |t|
  team = {}
  # team name
  team["name"] = (t.css('tr')[0].css('b').text).gsub(" roster", "")
  team_players_rows = t.css('table.sortable tr')
  team["players"] = []
  # Skip header and iterate over players
  team_players_rows.drop(1).each do |tp|
    team["players"].push(tp.css('td')[2].css('a').text)
  end
@parsed_teams << team
end

@parsed_teams将是一个具有以下值的数组：

[{"name"=>"Boston Celtics", 
 "players"=>["Bass, Brandon", "Bogans, Keith", "Bradley, Avery", 
 "Brooks, MarShon", "Crawford, Jordan", "Faverani, Vítor", "Green, 
 Jeff", "Humphries, Kris", "Lee, Courtney", "Olynyk, Kelly", "Pressey, Phil", 
 "Rondo, Rajon", "Sullinger, Jared", "Wallace, Gerald"]},       
 {"name"=>"Brooklyn Nets",...]