The Searchable
module declares the interface used for searching your DOM.
It implements the public methods ‘search`, `css`, and `xpath`, as well as allowing specific implementations to specialize some of the important behaviors.
Regular expression used by Searchable#search
to determine if a query string is CSS
or XPath
# File lib/nokogiri/xml/searchable.rb, line 185 def >(selector) # rubocop:disable Naming/BinaryOperatorParameterName ns = (document.root&.namespaces || {}) xpath(CSS.xpath_for(selector, prefix: "./", ns: ns).first) end
Search this node’s immediate children using CSS
selector selector
# File lib/nokogiri/xml/searchable.rb, line 74 def at(*args) search(*args).first end
Search this object for paths
, and return only the first result. paths
must be one or more XPath
or CSS
queries.
See Searchable#search
for more information.
# File lib/nokogiri/xml/searchable.rb, line 128 def at_css(*args) css(*args).first end
Search this object for CSS
rules
, and return only the first match. rules
must be one or more CSS
selectors.
See Searchable#css
for more information.
# File lib/nokogiri/xml/searchable.rb, line 177 def at_xpath(*args) xpath(*args).first end
Search this node for XPath
paths
, and return only the first match. paths
must be one or more XPath
queries.
See Searchable#xpath
for more information.
# File lib/nokogiri/xml/searchable.rb, line 114 def css(*args) rules, handler, ns, _ = extract_params(args) css_internal(self, rules, handler, ns) end
Search this object for CSS
rules
. rules
must be one or more CSS
selectors. For example:
node.css('title') node.css('body h1.bold') node.css('div + p.green', 'div#one')
A hash of namespace bindings may be appended. For example:
node.css('bike|tire', {'bike' => 'http://schwinn.com/'})
Custom CSS
pseudo classes may also be defined. To define custom pseudo classes, create a class and implement the custom pseudo class you want defined. The first argument to the method will be the current matching NodeSet
. Any other arguments are ones that you pass in. For example:
node.css('title:regex("\w+")', Class.new { def regex node_set, regex node_set.find_all { |node| node['some_attribute'] =~ /#{regex}/ } end }.new)
Note that the CSS
query string is case-sensitive with regards to your document type. That is, if you’re looking for “H1” in an HTML
document, you’ll never find anything, since HTML
tags will match only lowercase CSS
queries. However, “H1” might be found in an XML
document, where tags names are case-sensitive (e.g., “H1” is distinct from “h1”).
# File lib/nokogiri/xml/searchable.rb, line 54 def search(*args) paths, handler, ns, binds = extract_params(args) xpaths = paths.map(&:to_s).map do |path| LOOKS_LIKE_XPATH.match?(path) ? path : xpath_query_from_css_rule(path, ns) end.flatten.uniq xpath(*(xpaths + [ns, handler, binds].compact)) end
Search this object for paths
. paths
must be one or more XPath
or CSS
queries:
node.search("div.employee", ".//title")
A hash of namespace bindings may be appended:
node.search('.//bike:tire', {'bike' => 'http://schwinn.com/'}) node.search('bike|tire', {'bike' => 'http://schwinn.com/'})
For XPath
queries, a hash of variable bindings may also be appended to the namespace bindings. For example:
node.search('.//address[@domestic=$value]', nil, {:value => 'Yes'})
Custom XPath
functions and CSS
pseudo-selectors may also be defined. To define custom functions create a class and implement the function you want to define. The first argument to the method will be the current matching NodeSet
. Any other arguments are ones that you pass in. Note that this class may appear anywhere in the argument list. For example:
node.search('.//title[regex(., "\w+")]', 'div.employee:regex("[0-9]+")' Class.new { def regex node_set, regex node_set.find_all { |node| node['some_attribute'] =~ /#{regex}/ } end }.new )
See Searchable#xpath
and Searchable#css
for further usage help.
# File lib/nokogiri/xml/searchable.rb, line 163 def xpath(*args) paths, handler, ns, binds = extract_params(args) xpath_internal(self, paths, handler, ns, binds) end
Search this node for XPath
paths
. paths
must be one or more XPath
queries.
node.xpath('.//title')
A hash of namespace bindings may be appended. For example:
node.xpath('.//foo:name', {'foo' => 'http://example.org/'}) node.xpath('.//xmlns:name', node.root.namespaces)
A hash of variable bindings may also be appended to the namespace bindings. For example:
node.xpath('.//address[@domestic=$value]', nil, {:value => 'Yes'})
Custom XPath
functions may also be defined. To define custom functions create a class and implement the function you want to define. The first argument to the method will be the current matching NodeSet
. Any other arguments are ones that you pass in. Note that this class may appear anywhere in the argument list. For example:
node.xpath('.//title[regex(., "\w+")]', Class.new { def regex node_set, regex node_set.find_all { |node| node['some_attribute'] =~ /#{regex}/ } end }.new)
© 2008–2018 Aaron Patterson, Mike Dalessio, Charles Nutter, Sergio Arbeo,
Patrick Mahoney, Yoko Harada, Akinori MUSHA, John Shahid, Lars Kanis
Licensed under the MIT License.
https://nokogiri.org/rdoc/Nokogiri/XML/Searchable.html