@version ||= version

# -*- encoding : utf-8 -*-
class InterfaceBaseController < ActionController::Base

private
def set_version
version = params[:version] || '1.8.0'
ua = params[:ua] || ''

@version = if ua == 'xxx'
'1.8.0' if version >= '2.1.0'
elsif ua == '111'
'1.8.0' if version >= '1.1.1'
end

@version ||= version
end

end

before_filter :set_version, only: [:all_channels]

#可以直接使用@version来替代params[:version]