Jav*_*ier 5 ruby regex xpath ruby-on-rails nokogiri
我使用Nokogiri(Rubygem)css搜索来查找<div>我的html中的某些内容.看起来Nokogiri的css搜索不喜欢正则表达式.我想切换到Nokogiri的xpath搜索,因为这似乎支持搜索字符串中的正则表达式.
如何在xpath搜索中实现下面提到的(伪)css搜索？
require 'rubygems'
require 'nokogiri'
value = Nokogiri::HTML.parse(<<-HTML_END)
"<html>
<body>
<p id='para-1'>A</p>
<p id='para-22'>B</p>
<h1>Bla</h1>
<p id='para-3'>C</p>
<p id='para-4'>D</p>
<div class="foo" id="eq-1_bl-1">
<p id='para-5'>3</p>
</div>
</body>
</html>"
HTML_END
# my_block is given
my_bl = "1"
# my_eq corresponds to this regex
my_eq = "\/[0-9]+\/"
# FIXME The following line should be changed to an xpath search.
if my_div = value.css("div#eq-#{my_eq}_bl-#{my_bl}.foo").first
# doing some stuff with the <p> inside the div
end
Mike Dalessio(Nokogiri核心开发人员的一半)给了我答案#nokogiri(irc.freenode.net).看起来Nokogiri CSS和XPath搜索都不支持正则表达式匹配.这是他如何使用Nokogiri搜索正则表达式的解决方案:
require 'rubygems'
require 'nokogiri'
value = Nokogiri::HTML.parse(<<-HTML_END)
"<html>
<body>
<p id='para-1'>A</p>
<p id='para-22'>B</p>
<h1>Bla</h1>
<p id='para-3'>C</p>
<p id='para-4'>D</p>
<div class="foo" id="eq-1_bl-1">
<p id='para-5'>3</p>
</div>
<div class="bar" id="eq-1_bl-1">
<p id='para-5'>3</p>
</div>
</body>
</html>"
HTML_END
# my_block is given
my_bl = "1"
# my_eq corresponds to this regex
my_eq = "[0-9]+"
# full regex to search for in node ids
full_regex = %r(eq-#{my_eq}_bl-#{my_bl})
filter_by_id = Class.new do
attr_accessor :matches
def initialize(regex)
@regex = regex
@matches = []
end
def filter(node_set)
@matches += node_set.find_all { |x| x['id'] =~ @regex }
end
end.new(full_regex)
value.css("div.foo:filter()", filter_by_id)
filter_by_id.matches.each do |node|
puts node
end