Question

编辑：我设法删除了！我必须将实例变量@movies = Movie.find（params [：id]）定义为控制器中的delete方法。

我仍然无法更新。我得到“param缺失或价值为空：电影”

我忘了添加我的控制器！遗憾！

我正在尝试将我的课堂练习复制到另一个应用程序中，以便练习。

这个想法是能够将新电影添加到数据库中，并获得更新其信息的选项，并删除它们。我可以添加新内容，但我无法更新或删除它们。

感谢我能得到的任何输入。

的routes.rb

Rails.application.routes.draw do

  root "movies#index"
  get "/movies", to: "movies#index"
  get "/movies/new", to: "movies#new", as: "new_movie"
  get '/movies/:id', to: "movies#movie_page", as: "movie_page"
  post "/movies", to: "movies#add"
  get "/movies/:id/edit", to: "movies#edit", as: "movie_edit"
  put "/movies/:id", to: "movies#update"
  patch "/movies/:id", to: "movies#update", as: "update_movie"
  delete "/movies/:id", to: "movies#delete", as: "delete_movie"

end

控制器

class MoviesController < ApplicationController

    def index
        @movies = Movie.all
    end

    def movie_page
        @movies = Movie.find(params[:id])
    end

    def new
        @movies = Movie.new
    end

    def add
        @movies = Movie.create(movie_params)
        redirect_to movies_path
    end

    def edit
        @movies = Movie.find(params[:id])
    end

    def update
        @movies.update(movie_params)
        redirect_to @movies, notice: "Shirt was updated."
    end

    def delete
        @movies = Movie.find(params[:id])
        @movies.destroy
        # flash[:notice] = "Shirt was deleted."
        redirect_to root_path, notice: "Shirt was deleted."
    end

    def movie_params
        params.require(:movie).permit(:title, :description, :year_released)
    end

    # def set_movie
    #   @movies = Movie.find(params[:id])
    # end

end

表格部分

<%= form_for @movies do |m| %>
    <p>
        <%= m.label :title %><br>
        <%= m.text_field :title %>
    </p>
    <p>
        <%= m.label :description %><br>
        <%= m.text_field :description %>
    </p>
    <p>
        <%= m.label :year_released %><br>
        <%= m.text_field :year_released %>
    </p>
    <p>
        <%= m.submit %>
    </p>
<% end %>

电影页面html（个别电影，标有ID）**我无法更新或删除，没有路线匹配删除。

当我按更新时 - 我得到param缺失或值为空：电影

<h1><%= @movies.title %></h1>
<h2>Released on : <%= @movies.year_released %> </h2>
<p> <%= @movies.description %> </p>

<%= link_to "Update", movie_edit_path(@movies) %>
<%= link_to "Delete", movies_path, method: :delete %

编辑页面*我无法访问此链接。形式是问题

<h1>Edit <%= @movies.title %> Info </h1>

<%= render "form" %>

<%= link_to "Cancel Edit", movie_edit_path(@movies) %>

非常感谢你们

Answer 1

def update
  @movie = Move.find(params[:id])
  @movie.update(movie_params)
  redirect_to movie_path(@movie)
end

在您的路线上。您只需要resources :movies

你得到的param是空的，因为你必须传入要更新的电影的id。

Answer 2

主要问题是在使用之前不要从数据库加载变量@movies。

def update
    @movies.update(movie_params)
    redirect_to @movies, notice: "Shirt was updated."
end


def update
    @movies.find(params[:id])
    @movie.update(movie_params)
    redirect_to @movies, notice: "Shirt was updated."
end

除此之外，你还有大量的重复和相当多的特质。

Rails将这些命名约定用于操作：

索引
show（not movie_page）
新
创建（不添加）
修改
更新
销毁（不删除）

除非你有充分的理由不这样做，否则你应该遵循它们。

class MoviesController < ApplicationController

  # cuts the duplication
  before_filter :set_movie, except: [:new, :index]

  def index
    @movies = Movie.all
  end

  # GET /movies/:id
  def show
  end

  # GET /movies/new
  def new
    @movie = Movie.new
  end

  # POST /movies
  def create
    @movie = Movie.create(movie_params)
    redirect_to movies_path
  end

  # GET /movies/edit
  def edit
  end

  # PUT|PATCH /movies/:id
  def update
    @movie.update(movie_params)
    redirect_to @movie, notice: "Shirt was updated."
  end

  # DELETE /movies/:id
  def destroy
    @movie.destroy
    redirect_to action: :index 
  end

  private 

  def movie_params
    params.require(:movie).permit(:title, :description, :year_released)
  end

  def set_movie
    # Use the singular form when naming a variable with a single record
    # failure to do so may result in tarring and feathering
    @movie = Movie.find(params[:id])
  end 
end

Rails - 更新和删除内容？

2 个答案: