Module: EPUB::Parser::Utils

Included in:

ContentDocument, OCF, Publication

Defined in:

lib/epub/parser/utils.rb

Class Method Summary

• .extract_attribute(element, name, prefix = nil) ⇒ String

  Extract the value of attribute of element.

Class Method Details

.extract_attribute(element, name, prefix = nil) ⇒ String

TODO:

Refinement Nokogiri::XML::Node instead of use this method after Ruby 2.0 becomes popular

Extract the value of attribute of element

Parameters:

• element (Nokogiri::XML::Element)
• name (String) —

  name of attribute excluding namespace prefix

• prefix (String, nil) (defaults to: nil) —

  XML namespace prefix in NAMESPACES keys

Returns:

• (String) —

  value of attribute when the attribute exists

• nil when the attribute doesn’t exist

# File 'lib/epub/parser/utils.rb', line 13

def extract_attribute(element, name, prefix=nil)
  attr = element.attribute_with_ns(name, EPUB::NAMESPACES[prefix])
  attr.nil? ? nil : attr.value
end