%-
province = '440000'
city = '440300'
district = '440305'
provinces = ChinaCity.list
cities = ChinaCity.list(province)
districtes = ChinaCity.list(city)
%>
<%= select_tag :province, options_for_select(provinces, province) , prompt: '--省份--', class: ['city-select', 'city-province'] %>
<%= select_tag :city , options_for_select(cities, city) , prompt: '--城市--', class: ['city-select', 'city-city'] %>
<%= select_tag :district, options_for_select(districtes, district), prompt: '--地区--', class: ['city-select', 'city-district'] %>
--省份--
<%= options_for_select(ChinaCity.list, province) %>
--城市--
<%= options_for_select(cities, city) %>
--地区--
<%= options_for_select(districtes, district) %>