如何将一组放在中

我想通过使用以下Ruby代码和Nokogiri找到一种方法来获取HTML结果（下面进一步提到）：

require 'rubygems' require 'nokogiri' value = Nokogiri::HTML.parse(<<-HTML_END) "  
A
 
B
 
Bla
 
C
 
D
 
E
  " HTML_END # The selected-array is given by the application. # It consists of a sorted array with all ids of # 
 that need to be enclosed by the 
 selected = ["2","3","4"] first_p = selected.first last_p = selected.last # # WHAT RUBY CODE DO I NEED TO INSERT HERE TO GET # THE RESULTING HTML AS SEEN BELOW? # 

生成的HTML应如下所示（请注意插入的

）：

   
A
 
 
B
 
Bla
 
C
 
D
 
 
E
   

Answer 1

在这些情况下，您通常希望使用底层库为您提供的任何SAX接口 ，以有状态和连续的方式遍历和重写输入XML（或XHTML）：

 require 'nokogiri' require 'CGI' Nokogiri::XML::SAX::Parser.new( Class.new(Nokogiri::XML::SAX::Document) { def initialize first_p, last_p @first_p, @last_p = first_p, last_p end def start_document puts '' end def start_element name, attrs = [] attrs = Hash[*attrs] @depth += 1 unless @depth.nil? print '
' if name=='p' && attrs['id'] == @first_p @depth = 1 if name=='p' && attrs['id'] == @last_p && @depth.nil? print "<#{ [ name, attrs.collect { |k,v| "#{k}=\"#{CGI::escapeHTML(v)}\"" } ].flatten.join(' ') }>" end def end_element name @depth -= 1 unless @depth.nil? print "" if @depth == 0 print '
' @depth = nil end end def cdata_block string print "" end def characters string print CGI::escapeHTML(string) end def comment string print "" end }.new('2', '4') ).parse(<<-HTML_END)      "special" entities 
A
 
B
 
C
 
D
 
E
    HTML_END 

或者，您也可以使用DOM模型接口 （而不是SAX接口）将整个文档加载到内存中（与您在原始问题中开始执行的方式相同），然后执行节点操作（插入和删除）如下：

 require 'rubygems' require 'nokogiri' doc = Nokogiri::HTML.parse(<<-HTML_END)   
A
 
B
 
C
 
D
 
E
   HTML_END first_p = "2" last_p = "4" doc.css("p[id=\"#{first_p}\"] ~ p[id=\"#{last_p}\"]").each { |node| div_node = nil node.parent.children.each { |sibling_node| if sibling_node.name == 'p' && sibling_node['id'] == first_p div_node = Nokogiri::XML::Node.new('div', doc) sibling_node.add_previous_sibling(div_node) end unless div_node.nil? sibling_node.remove div_node << sibling_node end if sibling_node.name == 'p' && sibling_node['id'] == last_p div_node = nil end } } puts doc 

Answer 2

这是我在项目中实施的工作解决方案（Vlad @ SO＆Whitelist @ irc＃rubyonrails：感谢您的帮助和灵感。）：

 require 'rubygems' require 'nokogiri' value = Nokogiri::HTML.parse(<<-HTML_END) "  
A
 
B
 
Bla
 
C
 
D
 
E
  " HTML_END # The selected-array is given by the application. # It consists of a sorted array with all ids of # 
 that need to be enclosed by the 
 selected = ["2","3","4"] # We want an elements, not nodesets! # .first returns Nokogiri::XML::Element instead of Nokogiri::XML::nodeset first_p = value.css("p##{selected.first}").first last_p = value.css("p##{selected.last}").first parent = value.css('body').first # build and set new div_node div_node = Nokogiri::XML::Node.new('div', value) div_node['class'] = 'XYZ' # add div_node before first_p first_p.add_previous_sibling(div_node) selected_node = false parent.children.each do |tag| # if it's the first_p selected_node = true if selected.include? tag['id'] # if it's anything between the first_p and the last_p div_node.add_child(tag) if selected_node # if it's the last_p selected_node = false if selected.last == tag['id'] end puts value.to_html