Question

所以我循环遍历一个数组元素，这是返回的结果：

[nil, [#<Nokogiri::XML::Element:0x835386d4 name="a" attributes=[#<Nokogiri::XML::Attr:0x835385f8 name="href" value="http://bham.craigslist.org/web/2961573018.html">] children=[#<Nokogiri::XML::Text:0x835381c0 "Web Designer Full time">]>

我想要做的是访问href值，然后访问text值。我该怎么做？

我试过了：

puts i[:href]

但是这会产生这个错误：

TypeError: Symbol as array index

顺便说一句，我通过以下方式访问i作为数组中的元素：

contents.each do |i|
    puts i.inspect
    puts i[:href]
end

修改1：

这就是我生成contents数组的方法。没有必要重命名它，因为它可能会让人感到困惑：）

contents = {}
first_items.each do |link|
    content_url = link
    content_page = Nokogiri::HTML(open(content_url))
    contents[link[:href]] = content_page.css("p a")
end

puts contents.inspect

这是输出的结果：

{nil=>[#<Nokogiri::XML::Element:0x85fee914 name="a" attributes=[#<Nokogiri::XML::Attr:0x85fee838 name="href" value="http://bham.craigslist.org/web/2961573018.html">] children=[#<Nokogiri::XML::Text:0x85fee400 "Web Designer Full time">]>, #<Nokogiri::XML::Element:0x85fee298 name="a" attributes=[#<Nokogiri::XML::Attr:0x85fee1bc name="href" value="http://bham.craigslist.org/web/2959813303.html">] children=[#<Nokogiri::XML::Text:0x85fedd84 "Once in a lifetime opportunity...">]>, #<Nokogiri::XML::Element:0x85fedc1c name="a" attributes=[#<Nokogiri::XML::Attr:0x85fedb40 name="href" value="http://bham.craigslist.org/web/2925485723.html">] children=[#<Nokogiri::XML::Text:0x85fed708 "Website Designer and Blogging Internship!">]>, #<Nokogiri::XML::Element:0x85fed5a0 name="a" attributes=[#<Nokogiri::XML::Attr:0x85fed4c4 name="href" value="http://bham.craigslist.org/web/2918424652.html">] children=[#<Nokogiri::XML::Text:0x85fed08c "Excellent Java Developer Opportunity!">]>, #<Nokogiri::XML::Element:0x85fecf24 name="a" attributes=[#<Nokogiri::XML::Attr:0x85fece48 name="href" value="http://bham.craigslist.org/web/2888669703.html">] children=[#<Nokogiri::XML::Text:0x85feca10 "Freelance Graphic Design">]>, #<Nokogiri::XML::Element:0x85fec8a8 name="a" attributes=[#<Nokogiri::XML::Attr:0x85fec7cc name="href" value="http://bham.craigslist.org/web/2900256461.html">] children=[#<Nokogiri::XML::Text:0x85fec394 "GWT/GXT Developer">]>, #<Nokogiri::XML::Element:0x85fec22c name="a" attributes=[#<Nokogiri::XML::Attr:0x85fec150 name="href" value="http://bham.craigslist.org/web/2897641463.html">] children=[#<Nokogiri::XML::Text:0x85febd18 "Website hiring!">]>]}

以下是i的输出的完整值：

--------------------
This is the value of i: 
[nil, [#<Nokogiri::XML::Element:0x85fee914 name="a" attributes=[#<Nokogiri::XML::Attr:0x85fee838 name="href" value="http://bham.craigslist.org/web/2961573018.html">] children=[#<Nokogiri::XML::Text:0x85fee400 "Web Designer Full time">]>, #<Nokogiri::XML::Element:0x85fee298 name="a" attributes=[#<Nokogiri::XML::Attr:0x85fee1bc name="href" value="http://bham.craigslist.org/web/2959813303.html">] children=[#<Nokogiri::XML::Text:0x85fedd84 "Once in a lifetime opportunity...">]>, #<Nokogiri::XML::Element:0x85fedc1c name="a" attributes=[#<Nokogiri::XML::Attr:0x85fedb40 name="href" value="http://bham.craigslist.org/web/2925485723.html">] children=[#<Nokogiri::XML::Text:0x85fed708 "Website Designer and Blogging Internship!">]>, #<Nokogiri::XML::Element:0x85fed5a0 name="a" attributes=[#<Nokogiri::XML::Attr:0x85fed4c4 name="href" value="http://bham.craigslist.org/web/2918424652.html">] children=[#<Nokogiri::XML::Text:0x85fed08c "Excellent Java Developer Opportunity!">]>, #<Nokogiri::XML::Element:0x85fecf24 name="a" attributes=[#<Nokogiri::XML::Attr:0x85fece48 name="href" value="http://bham.craigslist.org/web/2888669703.html">] children=[#<Nokogiri::XML::Text:0x85feca10 "Freelance Graphic Design">]>, #<Nokogiri::XML::Element:0x85fec8a8 name="a" attributes=[#<Nokogiri::XML::Attr:0x85fec7cc name="href" value="http://bham.craigslist.org/web/2900256461.html">] children=[#<Nokogiri::XML::Text:0x85fec394 "GWT/GXT Developer">]>, #<Nokogiri::XML::Element:0x85fec22c name="a" attributes=[#<Nokogiri::XML::Attr:0x85fec150 name="href" value="http://bham.craigslist.org/web/2897641463.html">] children=[#<Nokogiri::XML::Text:0x85febd18 "Website hiring!">]>]]
--------------------
This is the value of i.href:

编辑2：

顺便说一句，这就是实际HTML输出的样子......我这样做了：

builder = Nokogiri::HTML::Builder.new do |doc|
    doc.html {
        doc.body {
            contents.each do |el|
                if !el.nil?
                    puts "-" * 20
                    puts "This is the value of el: "
                puts el.inspect

                    puts "-" * 20
                    puts "This is the value of el.href: "           
                 puts el[:href]
                end

                doc.p {
                    doc.a el, :href => el
                    } 
            end     
            }           
        }
end

puts "*" * 50
puts "This is the HTML generated"

puts builder.to_html

它的外观如下：

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" "http://www.w3.org/TR/REC-html40/loose.dtd">
<html><body><p><a href="&lt;a%20href=%22http://bham.craigslist.org/web/2961573018.html%22&gt;Web%20Designer%20Full%20time&lt;/a&gt;&lt;a%20href=%22http://bham.craigslist.org/web/2959813303.html%22&gt;Once%20in%20a%20lifetime%20opportunity...&lt;/a&gt;&lt;a%20href=%22http://bham.craigslist.org/web/2925485723.html%22&gt;Website%20Designer%20and%20Blogging%20Internship!&lt;/a&gt;&lt;a%20href=%22http://bham.craigslist.org/web/2918424652.html%22&gt;Excellent%20Java%20Developer%20Opportunity!&lt;/a&gt;&lt;a%20href=%22http://bham.craigslist.org/web/2888669703.html%22&gt;Freelance%20Graphic%20Design&lt;/a&gt;&lt;a%20href=%22http://bham.craigslist.org/web/2900256461.html%22&gt;GWT/GXT%20Developer&lt;/a&gt;&lt;a%20href=%22http://bham.craigslist.org/web/2897641463.html%22&gt;Website%20hiring!&lt;/a&gt;">&lt;a href="http://bham.craigslist.org/web/2961573018.html"&gt;Web Designer Full time&lt;/a&gt;&lt;a href="http://bham.craigslist.org/web/2959813303.html"&gt;Once in a lifetime opportunity...&lt;/a&gt;&lt;a href="http://bham.craigslist.org/web/2925485723.html"&gt;Website Designer and Blogging Internship!&lt;/a&gt;&lt;a href="http://bham.craigslist.org/web/2918424652.html"&gt;Excellent Java Developer Opportunity!&lt;/a&gt;&lt;a href="http://bham.craigslist.org/web/2888669703.html"&gt;Freelance Graphic Design&lt;/a&gt;&lt;a href="http://bham.craigslist.org/web/2900256461.html"&gt;GWT/GXT Developer&lt;/a&gt;&lt;a href="http://bham.craigslist.org/web/2897641463.html"&gt;Website hiring!&lt;/a&gt;</a></p></body></html>

Answer 1

我认为这可以简单得多。 Nokogiri已经解析了该文档并提供了访问内容的便捷方法。而不是循环，存储Nokogiri对象，然后尝试提取它们，为什么不尝试更直接的方法呢？

试试这段代码：

content_page.search(//a[@href]).map{ |el| [el[:href], el.text] }

这将创建包含文档中每个链接的文本和href的二维数组，这就是您在后续评论中所说的，您实际上正在努力。

Answer 2

也许这样，因为你的阵列中有一个奇怪的零。

contents.each do |i|
  if !i.nil?
    puts i.inspect
    puts i[:href]
  end
end

Edit1 ：实际上我认为你只需要做contents = contents[1]。

contents = contents[1]
contents.each do |i|
    puts i.inspect
    puts i[:href]
end

Answer 3

您可以使用compact删除nils：

nodes.compact.each do |node|
  puts node[:href], node.text
end

如何解析Nokogiri在Ruby中返回的这个数据结构？

3 个答案: