Question

无论我在哪里尝试，我都会收到NoMethodError。转到http://localhost:3000/会出现undefined method new_movie_rentals_path'错误。去某个地方，如http://localhost:3000/movies/5/rentals/new（并且应该有一个ID为5，我还尝试了许多其他数字）给了我一个undefined method 'title' for nil:NilClass。那么，我相信我遇到了一些路由错误？但我不确定。

movies_controller.rb

class MoviesController < ApplicationController
  def new
    @movie = Movie.new
    @movies = Movie.all
  end

  def create
    @movie = Movie.new(comment_params)
    if @movie.save
      redirect_to new_movie_path
    end
  end

  def comment_params
    params.require(:movie).permit(:title, :year)
  end

end

rentals_controller.rb

class RentalsController < ApplicationController

  class RentalsController < ApplicationController
    def new
      @movie = Movie.find(params[:movie_id])
      @rental = @movie.rentals.build
    end

    def create
      @movie = Movie.find(params[:movie_id])
      @rental = @movie.rentals.build(rental_params)
      if @rental.save
        redirect_to new_rental_path(@movie)
      end
    end


    def rental_params
      params.require(:rental).permit(:id, :borrowed_on, :returned_on, :movie_id)
    end

  end

end

（电影）new.html.erb

Enter new movie information <br>


<%= form_for @movie do |f| %>
  Title: <%= f.text_field :title %> <br>
  Year: <%= f.text_field :year %> <br>
  <%= f.submit %>
<% end %>

<hr>

List of all movies: <br>
<% if !@movies.blank? %>
  <table border=1>
    <tr>
      <th> Title </th>
      <th> Year </th>
    </tr>
  <% for item in @movies %>
    <tr>
      <td> <%= link_to new_movie_rentals_path(@movie) %> </td> 
      <td> <%= item.year %> </td>
    </tr>
  <% end %>
  </table

<% end %>

（出租）new.html.erb

Movie: <%= @movie.title %> <%= link_to "back", new_movie_path %>
<hr>

<%= form_for [@movie, @rental] do |f| %>
  Borrowed on: <%= f.text_field :borrowed_on %> <br>
  Returned on: <%= f.text_field :returned_on %> <br>
  <%= f.submit %>
<% end %>


Rentals: 
<% if !@movie.rentals.blank? %>
  <% for item in @movie.rentals %>
    <%= item.borrowed_on %>, <%= item.returned_on %> <br>
  <% end %>
<% else %>
  No rentals yet
<% end %>

的routes.rb

Rails.application.routes.draw do

  resources :movies do
    resources :rentals
  end

  root 'movies#new'

movie.rb

class Movie < ActiveRecord::Base
  has_many :rentals
end

rental.rb

class Rental < ActiveRecord::Base
  belongs_to :movie
end

rake routes：

Prefix Verb   URI Pattern                                  Controller#Action
    movie_rentals GET    /movies/:movie_id/rentals(.:format)          rentals#index
                  POST   /movies/:movie_id/rentals(.:format)          rentals#create
 new_movie_rental GET    /movies/:movie_id/rentals/new(.:format)      rentals#new
edit_movie_rental GET    /movies/:movie_id/rentals/:id/edit(.:format) rentals#edit
     movie_rental GET    /movies/:movie_id/rentals/:id(.:format)      rentals#show
                  PATCH  /movies/:movie_id/rentals/:id(.:format)      rentals#update
                  PUT    /movies/:movie_id/rentals/:id(.:format)      rentals#update
                  DELETE /movies/:movie_id/rentals/:id(.:format)      rentals#destroy
           movies GET    /movies(.:format)                            movies#index
                  POST   /movies(.:format)                            movies#create
        new_movie GET    /movies/new(.:format)                        movies#new
       edit_movie GET    /movies/:id/edit(.:format)                   movies#edit
            movie GET    /movies/:id(.:format)                        movies#show
                  PATCH  /movies/:id(.:format)                        movies#update
                  PUT    /movies/:id(.:format)                        movies#update
                  DELETE /movies/:id(.:format)                        movies#destroy
             root GET    /                                            movies#new

Answer 1

您应该尝试使用new_movie_rental_path

您也可以在此处查看约定：http://guides.rubyonrails.org/routing.html

Answer 2

您致电 new_movie_rentals_path 的地方尝试拨打 new_movie_rental_path

确保在 RentalsController 的新操作中找到了电影

Rails：NoMethodError（s）。无法访问网页

2 个答案: