與引入nokogiri解析成其中存在在某一列

Question

林試圖解析標籤不與引入nokogiri一個表中的每個小區的多個標籤的表，其中有多於一個僅在一個TD字段：

<tr class="alt2"> 
     <td class="company">ABB Shanghai Transformer Co., Ltd.</td> 
     <td class="contactperson">Mr. Frank Liang<br/></td> 
     <td class="businesscategory"> 
     <label><code>C27.11 </code>Manufacture of electric motors, generators and transformers</label> 
     <label><code>C27.33 </code>Manufacture of wiring devices</label> 
     </td> 
    </tr> 

所以，我現在所做的是這樣的：

doc.css("tbody tr").each do |company| 
    new = GermanSubsidiary.new 
    new.name = company.at_css(".company").text 
    new.contact = company.at_css(".contactperson").text 
    company.at_css(".businesscategory label").each do |category| 
    new_class = BusinessClassification.create 
    new_class.code = category.at_css("code").text 
    new_class.name = category.text 
    end 
end 

不幸company.at_css(".businesscategory label").each do |category|不工作，因爲at_css不數組工作...是什麼呢？

我該如何深入分析結構？由於有多行表格，我必須在女巫行的目標中加以區分，並且不能在整個文檔中使用xpath命令。

由於馬庫斯

Answer 1

.at_css('.businesscategory label')僅返回第一個匹配節點。使用.css('.businesscategory label')得到所有匹配的節點

這個XML

xml = <<-XML 
<tbody> 
    <tr class="alt2"> 
    <td class="company">ABB Shanghai Transformer Co., Ltd.</td> 
    <td class="contactperson">Mr. Frank Liang<br/></td> 
    <td class="businesscategory"> 
     <label><code>C27.11 </code>Manufacture of electric motors, generators and transformers</label> 
     <label><code>C27.33 </code>Manufacture of wiring devices</label> 
    </td> 
    </tr> 
</tbody> 
XML 

這個腳本

require 'rubygems' 
require 'nokogiri' 
require 'pp' 

doc = Nokogiri::HTML.fragment(xml) 

puts "with at_css example:" 
doc.css("tbody tr").each do |company| 
    company.at_css(".businesscategory label").each do |category| 
    puts category.at_css("code").text 
    puts category.text 
    end 
end 

puts "\n\nwith css" 
doc.css("tbody tr").each do |company| 
    company.css(".businesscategory label").each do |category| 
    puts category.at_css("code").text 
    puts category.text 
    end 
end 

打印這個結果

with at_css example: 


with css 
C27.11 
C27.11 Manufacture of electric motors, generators and transformers 
C27.33 
C27.33 Manufacture of wiring devices 

所以，你可以看到，使用.css而不是.at_css將解決您的問題。

使用.at_css('.businesscategory').children將產生空白節點，所以一定要小心

puts "\n\nwith at_css().children" 
doc.css("tbody tr").each do |company| 
    company.at_css(".businesscategory").children.each do |category| 
    puts category.text.inspect 
    end 
end 

打印

with at_css().children 
"\n  " 
"C27.11 Manufacture of electric motors, generators and transformers" 
"\n  " 
"C27.33 Manufacture of wiring devices" 
"\n "