Question

我正在建立一个关于ROR5的简单问答论坛，我仍然坚持为每个问题提交一个答案。

在相应的问题/：id SHOW视图中，我有一个texteditor，用户可以在其中提交问题的答案。然后答案将发布到问题所在的同一页面。正如您在视图和答案控制器中看到的那样，我尝试通过答案控制器将表单链接到答案模型。

我似乎遇到了路由问题，因为当我点击“提交”时，我得到：

错误

param is missing or the value is empty: question

服务器日志

Started POST "/questions" for 127.0.0.1 at 2017-06-12 15:19:39 +0800
Processing by QuestionsController#create as HTML
Parameters: {"utf8"=>"✓", "authenticity_token"=>"bM4INetkQj94Hy1t64zVLEvIGCumUjLZpA6LwHNT0qTRjYHLYpkpcTw42ulOVNDePsYCAG5puco5AEl+nA6bGw==", "answer"=>{"answercontent"=>"<p>dqwdqwd</p>"}, "commit"=>"Submit"}
Completed 400 Bad Request in 5ms (ActiveRecord: 0.0ms)

ActionController::ParameterMissing (param is missing or the value is empty: question):

app/controllers/questions_controller.rb:24:in `question_params'
app/controllers/questions_controller.rb:16:in `create'

如何改进代码以解决此问题？

以下是我的代码的一部分：

/ questions /：id（显示视图）

<div class="description-wrap">
            <div class="description">
                <h1>Country:</h1> 
                <p><%= @question.country %></p>

                <h1>Educational Level:</h1> 
                <p><%= @question.educational_level %></p>

                <h1>Topic:</h1> 
                <p><%= @question.topic %></p>
            </div>

            <br> <!-- jQuery action to scroll down to text editor -->
            <a href=''><button type="button" class="btn">Answer this Question</button></a>

        </div>
    </div> 

   <!-- Omitted for brevity -->
   <!-- Answers submitted by users will be shown here -->

   <%= user.profilepicture_url %>
   <%= user.userid %>
   <%= answer.answercontent %>

   <!-- Submit Answer Form -->
   <div class="col-lg-10 col-sm-10 editor">    
        <%= form_for :answer, url: {action: "create"} do |f| %>
            <%= f.text_area :answercontent, :class => "tinymce", :rows => 10, :cols => 90 %> 
            <%= tinymce %>
            <%= f.submit "Submit", class: "btn btn-default" %>
        <% end %>
   </div>

如您所见，我在文本区域使用TinyMCE编辑器。这很好。

问题模型

问题模型有五个参数：

t.string :picture_url
t.string :country
t.string :educational_level
t.string :topic
t.integer :user_id

questions_controller.rb

控制器看起来像这样

class QuestionsController < ApplicationController

def index
    @question = Question.all
end

def show
    @question = Question.find(params[:id])
end

def new
    @question = Question.new
end

def create
  @question = Question.new(question_params)

  @question.save
  redirect_to @question
end

private
  def question_params
    params.require(:question).permit(:picture_url, :country, :educational_level, :topic)
  end
end

答案模型

答案模型有3个参数：

t.integer :user_id
t.integer :question_id
t.string :answercontent

answers_controller.rb

控制器看起来像这样。

class AnswersController < ApplicationController

def new
    # i think something is wrong here too..
    @answer = Question.show
end

def create
  @answer = Answer.new(answer_params)
    render :new

  @answer.save
  # is this part correct?
  redirect_to "/questions/#{question.id}"
end

private
  def answer_params
    params.require(:question).permit(:user_id, :question_id, :answercontent)
  end
end

的routes.rb

Rails.application.routes.draw do
root 'home#index'

get 'profile/index' => 'profile#index'

# is this 'post' route correct?
post 'questions/:id' => "answers#create"

resources :users 
resources :questions 
resources :answers

end

另外，如果我能以任何方式改进这个问题，请发表评论。感谢。

Answer 1

param丢失或值为空：问题

对于错误，您要将表单提交到questions#create而不是answers#create，因此question_params期望:question密钥出现在params hash中，错误也是如此。

您应该编辑如下表格

<%= form_for :answer, url: answers_path do |f| %>
  <%= f.text_area :answercontent, :class => "tinymce", :rows => 10, :cols => 90 %>
  <%= f.hidden_field :question_id, @question.id %>
  <%= tinymce %>
  <%= f.submit "Submit", class: "btn btn-default" %>
<% end %>

同样在answers_controller中，您的answer_params应该是这样的

def answer_params
  params.require(:answer).permit(:user_id, :question_id, :answercontent)
end

你的answers#create错了，它应该在下面

def create
  @question = Question.find(params[:answer][:question_id]
  @answer = Answer.new(answer_params)
  if @answer.save
    redirect_to @question
  else
    render :new #you might have to consider changing this to suite your case
  end
end

另外，虽然它与你正在做的事情无关，但answers#new也是错误的。它应该是

def new
  @answer = Answer.new
end

在Ruby on Rails 5

错误