我只贴相关代码： #event_attendees_controller.rb

class EventAttendeesController < ApplicationController
  def edit
    @attendee = @event.attendees.find(params[:id])
    if @attendee == nil
      throw "Attendee with id #{params[:id]} not found"
    else
      logger.info "Attendee with id #{params[:id]} is : #{@attendee.to_xml}"
    end
  end

  private
  def find_event
    @event = Event.find(params[:event_id])
  end
end

#event.rb

class Event < ActiveRecord::Base
   has_many :event_attendees
  def attendees
    return event_attendees
  end
end

#event_attendees/edit.html.erb

<%= form_for @attendee, :url => event_attendee_path(@event, @event_attendee), :method => :put do |f| %>
    <%= f.label :name, "Name" %>
    <%= f.text_field :name %>
    <%= f.submit %>
<% end %>

#event_attendees/index.html.erb

<ul>
  <% @attendees.each do |attendee| %>
    <li>
      <%= attendee.name %>
      <%= link_to "Show", event_attendee_path(@event, attendee)%>
      <%= link_to "Edit", edit_event_attendee_path(@event, attendee) %>
      <%= link_to "Delete", event_attendee_path(@event, attendee), :method => :delete %>
    </li>
  <% end %>
</ul>
<%= link_to "New Attendee", new_event_attendee_path(@event) %>

#event_attendee.rb

class EventAttendee < ActiveRecord::Base
  attr_accessible :name
  belongs_to :event
end

#routes.rb

resources :events do
    resources :attendees, :controller => :event_attendees
end

当在 index 页面点击 Edit 按钮的时候提示： No route matches {:action=>"show", :controller=>"event_attendees", :event_id=>#, :id=>nil} 很奇怪为什么传过来的 event_attendee 的 id 是 nil，但通过调试发现 controller 里面的 id 不是 nil，各位大牛能解释解释吗？