Ruby on rails 基于主题的Rails URL路由和分组帖子

我是rails新手，我使用scaffold创建了post模型并发布了名为string、EMail:string、Message:text、topic\u id:integer列的控制器

我还创建了一个主题模型和主题控制器，其中包含主题名称：string

我提供了模型之间的关系，如下所示：

class Topic < ActiveRecord::Base
    has_many :posts, foreign_key: 'topic_id'
end   

class Post < ActiveRecord::Base
    belongs_to :topic   
end

主题\u controller.rb代码：

我需要使用主题对帖子进行分组。i、 例如，单击某个特定主题上的显示，它应该转到URL/topics//posts，在那里它应该列出与该主题相关的所有帖子，我可以创建/删除属于该主题的帖子

有人能帮忙吗。。

---

谢谢。

您的问题应该更直接，有很多信息与问题无关，例如属性名称，您的目标不够明确

看来你只是想设置路线，对吧？通过关联：topic.posts，您已经拥有与该主题相关的所有帖子。您只需为帖子设置路由：

resources :topics do
  resources :posts
end

此外，由于您使用的是命名约定，因此不需要使用foreign_key选项。似乎您还可以用大写字母命名一些属性，它们应该是name、email和message

更新：

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在索引操作中，由于您希望帖子属于一个主题，因此需要确定@posts实例变量的范围。因为您使用的是嵌套资源，所以您有参数params[：topic_id]，所以只需使用@topic=topic.findparams[：topic_id]获取主题，然后使用@posts=@topic.posts确定关联范围。您需要对其他每个操作执行相同的操作。我建议您阅读一下Rails中的关联，您可能需要使用@topic.posts.build和@topic.posts.findparams[：id]等方法。

我在这个链接中找到了解决此问题的方法：

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下载源代码并找到解决方案…

当我单击“显示”时，您能告诉我这方面的代码吗？它只显示URL topics/topic\u id中的主题名称

class TopicsController < ApplicationController
  before_action :set_topic, only: [:show, :edit, :update, :destroy]

  # GET /topics
  # GET /topics.json
  def index
    @topics = Topic.all
  end

  # GET /topics/1
  # GET /topics/1.json
  def show
  end

  # GET /topics/new
  def new
    @topic = Topic.new
  end

  # GET /topics/1/edit
  def edit
  end

  # POST /topics
  # POST /topics.json
  def create
    @topic = Topic.new(topic_params)

    respond_to do |format|
      if @topic.save
        format.html { redirect_to @topic, notice: 'Topic was successfully         created.' }
        format.json { render :show, status: :created, location: @topic }
      else
        format.html { render :new }
        format.json { render json: @topic.errors, status: :unprocessable_entity }
      end
    end
  end

  # PATCH/PUT /topics/1
  # PATCH/PUT /topics/1.json
  def update
    respond_to do |format|
      if @topic.update(topic_params)
        format.html { redirect_to @topic, notice: 'Topic was successfully updated.' }
        format.json { render :show, status: :ok, location: @topic }
      else
        format.html { render :edit }
        format.json { render json: @topic.errors, status: :unprocessable_entity }
      end
    end
  end

  # DELETE /topics/1
  # DELETE /topics/1.json
  def destroy
    @topic.destroy
    respond_to do |format|
      format.html { redirect_to topics_url, notice: 'Topic was successfully destroyed.' }
      format.json { head :no_content }
    end
  end

  private
    # Use callbacks to share common setup or constraints between actions.
    def set_topic
      @topic = Topic.find(params[:id])
    end

    # Never trust parameters from the scary internet, only allow the white list through.
    def topic_params
      params.require(:topic).permit(:Name)
    end
end

class PostsController < ApplicationController
  before_action :set_post, only: [:show, :edit, :update, :destroy]

  # GET /posts
  # GET /posts.json
  def index
    @posts = Post.all
  end

  # GET /posts/1
  # GET /posts/1.json
  def show

  end

  # GET /posts/new
  def new
    @post = Post.new
  end

  # GET /posts/1/edit
  def edit
  end

  # POST /posts
  # POST /posts.json
  def create
    @post = Post.new(post_params)
    respond_to do |format|
      if @post.save
        format.html { redirect_to @post, notice: 'Post was successfully created.' }
        format.json { render :show, status: :created, location: @post }
      else
        format.html { render :new }
        format.json { render json: @post.errors, status: :unprocessable_entity }
      end
    end
  end

  # PATCH/PUT /posts/1
  # PATCH/PUT /posts/1.json
  def update
    respond_to do |format|
      if @post.update(post_params)
        format.html { redirect_to @post, notice: 'Post was successfully updated.' }
        format.json { render :show, status: :ok, location: @post }
      else
        format.html { render :edit }
        format.json { render json: @post.errors, status: :unprocessable_entity }
      end
    end
  end

  # DELETE /posts/1
  # DELETE /posts/1.json
  def destroy
    @post.destroy
respond_to do |format|
      format.html { redirect_to posts_url, notice: 'Post was successfully destroyed.' }
      format.json { head :no_content }
    end
  end

  private
    # Use callbacks to share common setup or constraints between actions.
    def set_post
      @post = Post.find(params[:id])
    end

    # Never trust parameters from the scary internet, only allow the white list through.
    def post_params
      params.require(:post).permit(:Name, :Email, :Message, :topic_id)
    end
end

resources :topics do
  resources :posts
end