Method: Nokogiri::XML::NodeSet#attr

Defined in:

lib/nokogiri/xml/node_set.rb

#attr(key, value = nil, &block) ⇒ Object Also known as: set, attribute

Set attributes on each Node in the NodeSet, or get an attribute from the first Node in the NodeSet.

To get an attribute from the first Node in a NodeSet:

node_set.attr("href") # => "https://www.nokogiri.org"

Note that an empty NodeSet will return nil when #attr is called as a getter.

To set an attribute on each node, key can either be an attribute name, or a Hash of attribute names and values. When called as a setter, #attr returns the NodeSet.

If key is an attribute name, then either value or block must be passed.

If key is a Hash then attributes will be set for each key/value pair:

node_set.attr("href" => "https://www.nokogiri.org", "class" => "member")

If value is passed, it will be used as the attribute value for all nodes:

node_set.attr("href", "https://www.nokogiri.org")

If block is passed, it will be called on each Node object in the NodeSet and the return value used as the attribute value for that node:

node_set.attr("class") { |node| node.name }

# File 'lib/nokogiri/xml/node_set.rb', line 203

def attr(key, value = nil, &block)
  unless key.is_a?(Hash) || (key && (value || block))
    return first&.attribute(key)
  end

  hash = key.is_a?(Hash) ? key : { key => value }

  hash.each do |k, v|
    each do |node|
      node[k] = v || yield(node)
    end
  end

  self
end