Ruby on Rails如何将单选按钮选中值传递到指定控制器方法

路由配置修正 #

你当前请求未命中do方法的核心原因是路由表中没有对应动作的匹配规则，且do是Ruby内置关键字，不适合作为控制器动作名，建议替换为check_answer：

1. 修改routes.rb，新增提交答案的POST路由：

Rails.application.routes.draw do
  root to: 'home_page#index' 
  
  get 'show_url/:id', to: 'quiz#show'
  # 优化show路由的参数规范
  get    '/show/:id', to: 'quiz#show'
  get    '/quiz',  to: 'quiz#index'
  # 新增答案校验路由
  post   '/quiz/check_answer', to: 'quiz#check_answer'
end

2. 修改quiz_controller.rb，将原do方法重命名为check_answer，补充业务逻辑：

class QuizController < ApplicationController
  def show
    # 配合优化后的路由，用params[:id]取题目ID，更规范
    @questions = Question.find(params[:id])
  end

  def show_url
    redirect_back(fallback_location: root_path)
  end

  def index
    @questions = Question.all
    Question.logic
  end

  def check_answer
    # 获取提交的参数
    current_question = Question.find(params[:question_id])
    user_selected = params[:selected_answer]
    # 此处假设Question模型有correct_answer字段存储正确选项的键，和单选框value对应
    is_correct = (user_selected == current_question.correct_answer)
    # 可根据需求返回JSON或跳转页面，此处以同步跳转为例
    if is_correct
      flash[:notice] = "回答正确"
    else
      flash[:alert] = "回答错误"
    end
    redirect_to quiz_path
  end
private
end

视图层调整 #

建议替换原来的link_to_remote写法，用Rails标准的表单提交，保证参数能正确传递，修改show.html.erb代码：

<h1>Questions</h1>
<%= @questions.question %>

<div class="container mt-sm-5 my-1">
  <div class="question ml-sm-5 pl-sm-5 pt-2">
    <div class="py-2 h5"><b></b></div>
    <%= form_with url: quiz_check_answer_path, method: :post, local: true do |f| %>
      <!-- 传递当前题目ID给控制器 -->
      <%= hidden_field_tag :question_id, @questions.id %>
      <div class="ml-md-3 ml-sm-3 pl-md-5 pt-sm-0 pt-3" id="options"> 
        <% str = @questions.answers.to_s %>
        <% pairs = str.split(',').map { |pair| pair.split('=>') }%>
        <% pairs.each do |sub_array| %>
          <label class="options"> <%= sub_array[1] if sub_array[1] != "nil" %>
            <input type="radio" name="selected_answer" value="<%= sub_array[0] if sub_array[0] != "nil" %>" required> 
            <span class="checkmark"></span> 
          </label> 
        <% end %>
      </div>
      <div class="d-flex align-items-center pt-3">
        <%= f.submit 'Submit now', class: 'btn btn-success' %>
      </div>
    <% end %>
  </div>
</div>

可选调整（index页面跳转） #

配合优化后的show路由，修改index.html.erb的跳转链接：

<td><%= link_to 'Question', show_path(q.id), method: :get %></td>

内容的提问来源于stack exchange，提问作者Andrew