Ruby on rails Rails 4:form_用于嵌套模型

我有三种型号：客户、汽车和ParkingRate。客户有很多车，而且车有很多停车费。我在客户端页面上有一个表单，它创建了一个与该客户端关联的汽车。我不知道如何在表单中添加一个停车费率字段，这样当为该客户创建一辆车时，也会为该车创建一个停车费率

我的代码如下所示：

client.rb

class Client < ActiveRecord::Base
  has_many :cars, dependent: destroy
end

class客户端

car.rb

class Car < ActiveRecord::Base
  belongs_to :client
  has_many :parking_rates
end

class-Car

停车费

class ParkingRate < ActiveRecord::Base
  belongs_to :car
end

class ParkingRate

在客户端页面（client/：id），我有一个表单来创建与该客户端关联的汽车，如下所示：

视图/客户端/show.html.erb：

<h1>Client information</h1>
... client info ...
<%= render 'cars/form' %>

<%= form_for([@client, @client.cars.build]) do |f| %>
  <p>
    <%= f.label :vehicle_id_number %><br>
    <%= f.text_field :vehicle_id_number %>
  </p>
  <p>
    <%= f.label :enter_date %><br>
    <%= f.text_field :enter_date %>
  </p>
  <p>
    <%= f.submit %>
  </p>
<% end %>

客户端信息
... 客户信息。。。

视图/cars/_form.html.erb：

<h1>Client information</h1>
... client info ...
<%= render 'cars/form' %>

<%= form_for([@client, @client.cars.build]) do |f| %>
  <p>
    <%= f.label :vehicle_id_number %><br>
    <%= f.text_field :vehicle_id_number %>
  </p>
  <p>
    <%= f.label :enter_date %><br>
    <%= f.text_field :enter_date %>
  </p>
  <p>
    <%= f.submit %>
  </p>
<% end %>

客户机和汽车控制器如下所示：

clients_controller.rb：

class ClientsController < ApplicationController

def new
  @client = Client.new
end

def create
  @client = Client.new(client_params)
  if @client.save
    redirect_to @client
  else
    render 'new'
  end
end

def show
  @client = Client.find(params[:id])
end

def index
  @clients = Client.all
end

def edit
  @client = Client.find(params[:id])
end

def update
  @client = Client.find(params[:id])

  if @client.update(client_params)
    redirect_to @client
  else
    render 'edit'
  end
end

def destroy
  @client = Client.find(params[:id])
  @client.destroy

  redirect_to clients_path
end

private
  def client_params
    params.require(:client).permit(:first_name, :last_name)
  end
end

class CarsController < ApplicationController

def create
  @client = Client.find(params[:client_id])
  @car = @client.cars.create(car_params)
  @parking_rate = @car.parking_rates.create(rate_params)
  redirect_to client_path(@client)
end

def show
  @client = Client.find(params[:client_id])
  @car = Car.find(params[:id])
end

def edit
  @client = Client.find(params[:client_id])
  @car = Car.find(params[:id])
end

def update
  @client = Client.find(params[:client_id])
  @car = Car.find(params[:id])
  @car.update(car_params)

  redirect_to client_path(@client)
end

def destroy
  @client = Client.find(params[:client_id])
  @car = @client.cars.find(params[:id])
  @car.destroy
  redirect_to client_path(@client)
end

private
  def car_params
    params.require(:car).permit(:vehicle_id_number, :enter_date, :rate)
  end

  def rate_params
    params.require(:parking_rate).permit(:rate)
  end
end

class客户端控制器

cars_controller.rb：

class ClientsController < ApplicationController

def new
  @client = Client.new
end

def create
  @client = Client.new(client_params)
  if @client.save
    redirect_to @client
  else
    render 'new'
  end
end

def show
  @client = Client.find(params[:id])
end

def index
  @clients = Client.all
end

def edit
  @client = Client.find(params[:id])
end

def update
  @client = Client.find(params[:id])

  if @client.update(client_params)
    redirect_to @client
  else
    render 'edit'
  end
end

def destroy
  @client = Client.find(params[:id])
  @client.destroy

  redirect_to clients_path
end

private
  def client_params
    params.require(:client).permit(:first_name, :last_name)
  end
end

class CarsController < ApplicationController

def create
  @client = Client.find(params[:client_id])
  @car = @client.cars.create(car_params)
  @parking_rate = @car.parking_rates.create(rate_params)
  redirect_to client_path(@client)
end

def show
  @client = Client.find(params[:client_id])
  @car = Car.find(params[:id])
end

def edit
  @client = Client.find(params[:client_id])
  @car = Car.find(params[:id])
end

def update
  @client = Client.find(params[:client_id])
  @car = Car.find(params[:id])
  @car.update(car_params)

  redirect_to client_path(@client)
end

def destroy
  @client = Client.find(params[:client_id])
  @car = @client.cars.find(params[:id])
  @car.destroy
  redirect_to client_path(@client)
end

private
  def car_params
    params.require(:car).permit(:vehicle_id_number, :enter_date, :rate)
  end

  def rate_params
    params.require(:parking_rate).permit(:rate)
  end
end

class CarsController

---

有了这个，我可以为给定的客户添加汽车，但我也希望在相同的表单上为汽车添加停车费。所以当我使用这个表单创建一辆车时，我想创建一个相关的停车率。助手的

表单使用
[@client，@client.comments.build]
作为模型对象，因此我不确定如何在同一表单中引用
停车费率
模型。我认为解决方案是为

助手使用一个

fields\u，它的模型参考是什么，我需要向汽车和客户控制器添加什么？
在client.rb中，添加行

accepts_nested_attributes_for :cars

已尝试在汽车模型中使用
accepts\u nested\u attributes\u:parking\u rates，dependent:destroy
。阅读上的Rails指南可以帮上大忙。