Question

我正在开发一款允许用户评论单个“工作”的应用（想想博客文章）。模型中的关联如下：

class User < ActiveRecord::Base
  has_many :works  
  has_many :comments


class Work < ActiveRecord::Base
  belongs_to :user
  has_many :comments

class Comment < ActiveRecord::Base
  belongs_to :user
  belongs_to :post
  belongs_to :work

Works show页面上有一个表单，允许用户发表评论：

<%= form_for(@comment) do |f| %>
  <%= render 'shared/error_messages', object: f.object %>
  <div class="field">
    <%= f.text_area :content, placeholder: "Post a comment!" %>
  </div>
  <%= f.submit "Post", class: "btn btn-small btn-primary" %>
<% end %>

Works控制器如下。请注意，我在这里添加了构建注释功能，以便Works页面上的表单起作用：

class WorksController < ApplicationController
   #before_filter :current_user,   only: [:edit, :update]

  def index
    @works = Work.all
    @comment = @work.comments.build(params[:comment])
    @comment.user = current_user

respond_to do |format|
  format.html # index.html.erb
  format.xml  { render :xml => @works }
end
end
def create
    @work = current_user.works.create(params[:work])
    redirect_to current_user
  end

def edit
    @work = current_user.works.find(params[:id])
end

def new
  @work = current_user.works.new
end

def destroy
  @work = current_user.works.find(params[:id]).destroy
  flash[:success] = "Work deleted"
  redirect_to current_user
end

 def update
    @work = current_user.works.find(params[:id])
    if @work.update_attributes(params[:work])
      flash[:success] = "Profile updated"
      redirect_to @work
    else
      render 'edit'
    end
  end


  def show 
  @work = Work.find(params[:id])
  @comment = @work.comments.build
  @comment.user = current_user
  @activities = PublicActivity::Activity.order("created_at DESC").where(trackable_type: "Work", trackable_id: @work).all
  @comments = @work.comments.order("created_at DESC").where(work_id: @work ).all 
    respond_to do |format|
      format.html # show.html.erb
      format.xml  { render :xml => @work }
    end
  end
end

最后，这是评论控制器：

class CommentsController < ApplicationController

  before_filter :authenticate_user!

  def index
    @comments = Comment.all
  end

  def show
    @comment = Comment.find(params[:id])
    @activities = PublicActivity::Activity.order("created_at DESC").where(trackable_type: "Comment", trackable_id: @comment).all
   respond_to do |format|
      format.html # show.html.erb
      format.xml  { render :xml => @comment }
  end

  def update
     @comment = current_user.comments.find(params[:id])
    if @comment.update_attributes(params[:comment])
      flash[:success] = "Comment updated"
      redirect_to @comment
    end
  end

  def create
    @work = Work.find(params[:id])
    @comment = @work.comments.build(params[:comment])
    @comment.user = current_user
    if @comment.save
      #flash[:success] = "Post created!"
      redirect_to @work
    else
      render 'home#index'
    end
  end
  end
end

当我尝试使用作品展示视图页面上的评论表单提交评论时，我收到以下错误：

在中的

Activerecord :: RecordNotFound

找不到没有ID的作品

为什么应用程序找不到Work，以便它可以将注释关联到它？

编辑1： 感谢下面的答案，我编辑了评论表：

<%= form_for(@work, @comment) do |f| %>
  <%= render 'shared/error_messages', object: f.object %>
  <div class="field">
    <%= f.text_area :content, placeholder: "Post feedback or contribute content
    to this work!" %>
  </div>
  <%= f.submit "Post", class: "btn btn-small btn-primary" %>
<% end %>

在对表单进行更改并添加嵌套路由后，我仍然遇到相同的错误。

我编辑了路线文件以包含工作评论的嵌套：

    authenticated :user do
    root :to => 'activities#index'
  end
  root :to => "home#index"
  devise_for :users
  resources :users do
    member do
      get :following, :followers, :posts, :comments
    end
  end
  resources :works do
    resources :comments
  end
  resources :relationships, only: [:create, :destroy]
  resources :posts
  resources :activities
  resources :comments

Rake路线显示以下注释#create： POST /comments(.:format）

POST URL（出现错误的地方）是appURL / works / 1 / comments

似乎不对。我需要改变什么？非常感谢你们的帮助！

Answer 1

您的表单必须为form_for([@work, @comment])，以便Rails知道如何构建/works/123/comments之类的网址。现在只需发布到/comments。

检查rake routes以查看CommentsController #create动作的路线。您可能还需要调整控制器以阅读params[:work_id]而不是params[:id]。

Answer 2

默认情况下，视图帮助器form_for(@comment)将发布到“/ comments”。您可以指定包含工作记录:id的网址（see the guides）。典型的方法是使用form_for([@work, @comment])，只要您使用注释作为嵌套的工作资源设置路由，Rails就会为您执行此操作。

ActiveRecord :: RecordNotFound - 没有ID就找不到

2 个答案: