ruby-on-railsrubystringformattingcase-conversion

Converting camel case to underscore case in ruby

Is there any ready function which converts camel case Strings into underscore separated string?

I want something like this:

"CamelCaseString".to_underscore

to return "camel_case_string".

...

Solution

  • Rails' ActiveSupport adds underscore to the String using the following: 

    class String
  def underscore
    self.gsub(/::/, '/').
    gsub(/([A-Z]+)([A-Z][a-z])/,'\1_\2').
    gsub(/([a-z\d])([A-Z])/,'\1_\2').
    tr("-", "_").
    downcase
  end
end

    Then you can do fun stuff: 

    "CamelCase".underscore
=> "camel_case"