Method: Nokogiri::XML::Node#add_class

Defined in:
lib/nokogiri/xml/node.rb

#add_class(names) ⇒ Object

:call-seq: add_class(names) → self

Ensure HTML CSS classes are present on self. Any CSS classes in names that already exist in the “class” attribute are not added. Note that any existing duplicates in the “class” attribute are not removed. Compare with #append_class.

This is a convenience function and is equivalent to:

node.kwattr_add("class", names)

See related: #kwattr_add, #classes, #append_class, #remove_class

Parameters

  • names (String, Array<String>)

    CSS class names to be added to the Node’s “class” attribute. May be a string containing whitespace-delimited names, or an Array of String names. Any class names already present will not be added. Any class names not present will be added. If no “class” attribute exists, one is created.

Returns

self (Node) for ease of chaining method calls.

Example: Ensure that the node has CSS class “section”

node                      # => <div></div>
node.add_class("section") # => <div class="section"></div>
node.add_class("section") # => <div class="section"></div> # duplicate not added

Example: Ensure that the node has CSS classes “section” and “header”, via a String argument

Note that the CSS class “section” is not added because it is already present. Note also that the pre-existing duplicate CSS class “section” is not removed.

node                             # => <div class="section section"></div>
node.add_class("section header") # => <div class="section section header"></div>

Example: Ensure that the node has CSS classes “section” and “header”, via an Array argument

node                                  # => <div></div>
node.add_class(["section", "header"]) # => <div class="section header"></div>
[View source]

790
791
792
 
# File 'lib/nokogiri/xml/node.rb', line 790

def add_class(names)
  kwattr_add("class", names)
end