Rails：如何从帮助器访问模型

Question

I have a constant defined in a Model, and need access to it from within a Helper. Is there a way to do this? Example:

#app/models/my_model.rb
class MyModel < ActiveRecord::Base
  VALUE = 3

  def self.get_value
    VALUE
  end
end

#app/helpers/users_helper.rb
module UsersHelper
  VALUE_V1 = MyModel.get_value
  VALUE_V2 = MyModel::VALUE
end

Both VALUE_V1, and VALUE_V2 fail for me (uninitialized constant).

Answer 1

You need to use top level namespace when referring a constant inside module.

So,

 value1 = ::MyModel.get_value

Also, as Vimsha commented you can use the constant directly, no need to define another constant.