【发布时间】：2016-11-03 20:08:49
【问题描述】：
我正在使用 Nokogiri 作为工具来帮助我完成我正在为学校工作的项目。目前，该项目的想法是在 HTML 文档中搜索用户提供的关键字。该函数将在 <body> 元素之后的 HTML 字符串中查找所有出现的关键字，除非该关键字出现在 HTML 标记中，然后用标记包围找到的字符串以“突出显示”关键字。现在我的代码失败了，错误调用堆栈非常大。主要错误是这样的：
Nokogiri::CSS::SyntaxError:unexpected'$'after''[:substring_match,"simple"]'(Nokogiri::CSS::SyntaxError)
我目前的方法：
require 'nokogiri'
file = File.open ("desktop/Personal/code.HTML")
@doc = Nokogiri::HTML(file)
puts @doc
puts "Welcome to the HTML keyword highlighter!"
puts "Please enter a keyword"
keyword = gets.chomp
highlight = "<span style='background-color: yellow; color: black'>#{keyword}</span>"
search = @doc.xpath("//body").search("[text()*=#{keyword}")
search.each do |node|
nodeN = node.name
nodeH = node.content.gsub(keyword, highlight)
node.replace(nodeH)
end
file.close
错误调用堆栈：
/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/gems/2. 0.0/gems/nokogiri-1.5.6/lib/nokogiri/css/parser_extras.rb:87:in `on_error': unexpected '$' after '[:substring_match, "simple"]' (Nokogiri::CSS::SyntaxError)
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/racc/parser.rb:258:in `_racc_do_parse_c'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/racc/parser.rb:258:in `do_parse'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/gems/2.0.0/gems/nokogiri-1.5.6/lib/nokogiri/css/parser_extras.rb:62:in `parse'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/gems/2.0.0/gems/nokogiri-1.5.6/lib/nokogiri/css/parser_extras.rb:79:in `xpath_for'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/gems/2.0.0/gems/nokogiri-1.5.6/lib/nokogiri/css.rb:23:in `xpath_for'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/gems/2.0.0/gems/nokogiri-1.5.6/lib/nokogiri/xml/node_set.rb:111:in `block (2 levels) in css'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/gems/2.0.0/gems/nokogiri-1.5.6/lib/nokogiri/xml/node_set.rb:109:in `map'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/gems/2.0.0/gems/nokogiri-1.5.6/lib/nokogiri/xml/node_set.rb:109:in `block in css'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/gems/2.0.0/gems/nokogiri-1.5.6/lib/nokogiri/xml/node_set.rb:239:in `block in each'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/gems/2.0.0/gems/nokogiri-1.5.6/lib/nokogiri/xml/node_set.rb:238:in `upto'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/gems/2.0.0/gems/nokogiri-1.5.6/lib/nokogiri/xml/node_set.rb:238:in `each'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/gems/2.0.0/gems/nokogiri-1.5.6/lib/nokogiri/xml/node_set.rb:105:in `css'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/gems/2.0.0/gems/nokogiri-1.5.6/lib/nokogiri/xml/node_set.rb:81:in `block in search'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/gems/2.0.0/gems/nokogiri-1.5.6/lib/nokogiri/xml/node_set.rb:80:in `each'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/gems/2.0.0/gems/nokogiri-1.5.6/lib/nokogiri/xml/node_set.rb:80:in `search'
from /Users/Eva/Desktop/Personal/Project_Nokogiri.rb:21:in `<main>'
任何关于如何防止这种情况的建议将不胜感激！我是编程、Ruby 和 Nokogiri 的新手，所以我对如何自己解决这个问题知之甚少。如果格式不好，请见谅。感谢您的帮助！
【问题讨论】：