Question

我无法在Rails应用程序中添加评论系统。我遵循Rails指南see rails guide started，甚至从一个新的Rails应用开始。但是我不确定我是否正确遵循了指南。请帮我弄清楚我在做什么错。

CommentsController

class CommentsController < ApplicationController
  def new
    @comment = Comment.new
  end

  def create
    @course = Course.find(params[:course_id])
    @comment = @course.comments.build(comment_params)
    respond_to do |format|
      if @comment.save
        format.html { redirect_to @course, notice: 'Comment was successfully created.' }
        format.json { render :show, status: :created, location: @course }
      else
        format.html { render :new }
        format.json { render json: @comment.errors, status: :unprocessable_entity }
      end
    end
  end

  private

  def comment_params
    params.require(:comment).permit(:content, :course_id)    
  end
end

模型课程

class Course < ApplicationRecord
  has_many :comments
end

模型评论

class Comment < ApplicationRecord
  belongs_to :course
  validates :comment, presence: true, length: { minimum: 10}
end

评论表

<%= simple_form_for([@course, @course.comments.build], remote: true) do |f| %>
  <div class="card my-4">
    <h5 class="card-header">Interaction</h5>
    <div class="card-body">     
      <div class="form-group">
        <%= f.input :content, required: true, input_html: { class: 'textarea' }, wrapper: false, label_html: { class: 'label' }, placeholder:'Ajouter une question ou un commentaire...' %>
      </div>
      <button type="submit" class="btn btn-primary"><i class="fa fa-location-arrow" aria-hidden="true"></i> Ajouter</button>
   </div>
  </div>
<% end %>

routes.rb

 Rails.application.routes.draw do
  resources :courses do
   resources :comments
  end   

  root to:'home#index'
end

schema.rb

create_table "comments", force: :cascade do |t|
    t.text "content"
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
    t.bigint "course_id"
    t.bigint "user_id"
  end

  create_table "courses", force: :cascade do |t|
    t.string "title"
    t.text "content"
    t.string "image_course"
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
    t.string "slug"
    t.bigint "matiere_id"
    t.bigint "user_id"
    t.index ["matiere_id"], name: "index_courses_on_matiere_id"
    t.index ["user_id"], name: "index_courses_on_user_id"
  end

控制台消息 注意：**** ROLLBACK **在线28 **

Started POST "/courses/4/comments" for ::1 at 2019-11-30 11:30:11 +0000
Processing by CommentsController#create as JS
  Parameters: {"utf8"=>"✓", "comment"=>{"content"=>"100 ans, c'est très long. Je vous présente un pays qui n'a mis que deux ans à devenir un pays du tiers monde issu d'un pays riche et développé. C'est toujours un pays du tiers monde. Fortement et fièrement."}, "course_id"=>"4"}
  Course Load (1.3ms)  SELECT  "courses".* FROM "courses" WHERE "courses"."id" = $1 LIMIT $2  [["id", 4], ["LIMIT", 1]]
  ↳ app/controllers/comments_controller.rb:27
   (0.8ms)  BEGIN
  ↳ app/controllers/comments_controller.rb:28
   (0.6ms)  ROLLBACK
  ↳ app/controllers/comments_controller.rb:28
Completed 500 Internal Server Error in 33ms (ActiveRecord: 3.2ms)



NoMethodError - undefined method `comment' for #<Comment:0x0000555ccc6a8528>
Did you mean?  content:
  app/controllers/comments_controller.rb:28:in `create'

source=rack-timeout id=ca133680-ce55-4b88-99ce-16fd3d1f01a0 timeout=15000ms service=130ms state=completed

但是我必须在其中定义评论

在终端错误消息上说：

 NoMethodError - undefined method `comment' for #<Comment:0x00007f04245dc0a8>
Did you mean?  content:
  app/controllers/comments_controller.rb:33:in `block in create'
  app/controllers/comments_controller.rb:32:in `create'

Answer 1

在Comment模型中，没有“ comment”字段。您只有一个“内容”字段。您的问题是

validates :comment ,presence:true,
                    length: { minimum: 10}

在您的评论模型中。我认为您的意思是

validates :content, presence:true,
                    length: { minimum: 10}

如何在我的应用程序ruby on rails中添加评论功能？

1 个答案: