Ruby on rails Rails回形针错误未定义方法`之前'；for false：将图像附着到模型时FalseClass_Ruby On Rails_Ruby_Ruby On Rails 4_Paperclip

Ruby on rails Rails回形针错误未定义方法`之前'；for false：将图像附着到模型时FalseClass

ruby-on-rails ruby ruby-on-rails-4

Ruby on rails Rails回形针错误未定义方法`之前'；for false：将图像附着到模型时FalseClass,ruby-on-rails,ruby,ruby-on-rails-4,paperclip,Ruby On Rails,Ruby,Ruby On Rails 4,Paperclip,我有一个名为Question的模型，我想用回形针（5.0.0）将文件附加到（图）上。保存模型时，我收到以下错误： undefined method `before' for false:FalseClass 我的模型： class Question < ActiveRecord::Base belongs_to :subject belongs_to :category has_attached_file :diagram validates_attachment_co

我有一个名为Question的模型，我想用回形针（5.0.0）将文件附加到（图）上。保存模型时，我收到以下错误：

undefined method `before' for false:FalseClass

我的模型：

class Question < ActiveRecord::Base
  belongs_to :subject
  belongs_to :category

  has_attached_file :diagram
  validates_attachment_content_type :diagram, :content_type => ["image/jpg", 
    "image/jpeg", "image/png"], if: :hasdiagram

end

我的表格：

<h1 align="center">Add a new question</h1>
  <div class="col-md-4 offset-md-4">
    <%= render 'shared/errors', object: @question %>
    <%= form_for @question, :url => { :controller => 'questions', :action => 'create'}, method: :post do |f| %>

      <div class="form-group" id="diagram-input">
        <%= f.file_field :diagram %>
      </div>

      <%= f.submit "Submit", class: "btn btn-success btn-block" %>
    <% end %>
  </div>

添加新问题
{:controller=>'questions'，:action=>'create'}，方法：：post do | f |%>

任何帮助都将不胜感激，谢谢

整个日志：

Started POST "/admin/add_question" for 10.240.1.4 at 2017-11-12 15:39:10 +0000
Cannot render console from 10.240.1.4! Allowed networks: 127.0.0.1, ::1, 127.0.0.0/127.255.255.255
Processing by QuestionsController#create as HTML
  Parameters: {"utf8"=>"✓", "authenticity_token"=>"AFcHCrw6Dthasdesh5DNgdsxmFICxxPznyXtPDtxnp8zokpyZSeRHqiGC+K4SBMHehxYBgUXra30KTCj/AxUg==", "question"=>{"subject_id"=>"39", "category_id"=>"1", "hasdiagram"=>"1", "diagram"=>#<ActionDispatch::Http::UploadedFile:0x007f8064f72100 @tempfile=#<Tempfile:/tmp/RackMultipart20171112-8403-ewq7ng.png>, @original_filename="187c38aa17afdc65ba5c1c5239219686.png", @content_type="image/png", @headers="Content-Disposition: form-data; name=\"question[diagram]\"; filename=\"187c38aa17afdc65ba5c1c5239219686.png\"\r\nContent-Type: image/png\r\n">, "question"=>"a", "option1"=>"a", "option2"=>"a", "option3"=>"a", "option4"=>"a"}, "commit"=>"Submit"}
Command :: file -b --mime '/tmp/c5769bbf6ba9051718d946344886703720171112-8403-1v5gz0n.png'
Completed 500 Internal Server Error in 13ms (ActiveRecord: 0.0ms)

NoMethodError (undefined method `before' for false:FalseClass):
  app/controllers/questions_controller.rb:11:in `create'


  Rendered /usr/local/rvm/gems/ruby-2.3.4/gems/actionpack-4.2.5/lib/action_dispatch/middleware/templates/rescues/_source.erb (6.0ms)
  Rendered /usr/local/rvm/gems/ruby-2.3.4/gems/actionpack-4.2.5/lib/action_dispatch/middleware/templates/rescues/_trace.html.erb (2.7ms)
  Rendered /usr/local/rvm/gems/ruby-2.3.4/gems/actionpack-4.2.5/lib/action_dispatch/middleware/templates/rescues/_request_and_response.html.erb (1.2ms)
  Rendered /usr/local/rvm/gems/ruby-2.3.4/gems/actionpack-4.2.5/lib/action_dispatch/middleware/templates/rescues/diagnostics.html.erb within rescues/layout (27.9ms)

2017年11月12日15:39:10+0000，10.240.1.4开始发布“/admin/add_question” 无法从10.240.1.4中渲染控制台！允许的网络：127.0.0.1，：：1127.0.0.0/127.255.255.255 问题控制器处理#创建为HTML 参数：{“utf8”=>“✓", "真实性令牌“=>”AFcHCrw6Dthasdesh5DNgdsxmFICxxPznyXtPDtxnp8zokpyZSeRHqiGC+K4SBMHehxYBgUXra30KTCj/AxUg=>，“问题”=>，“问题”=>，“主题id”=>“39”，“类别id”=>“1”，“图表”=>，“问题”=>“a”，“选项1”=>“a”，“选项2”=>“a”，“选项3”=>“a”，“选项4”=>“提交”} 命令：：文件-b--mime'/tmp/c5769bbf6ba9051718d946344886703720171112-8403-1v5gz0n.png' 在13毫秒内完成500个内部服务器错误（ActiveRecord:0.0毫秒） NoMethodError（未定义false的'before'方法：FalseClass）： app/controllers/questions\u controller.rb:11:in'create' Rendered/usr/local/rvm/gems/ruby-2.3.4/gems/actionpack-4.2.5/lib/action\u dispatch/middleware/templates/rescues//u source.erb（6.0ms） Rendered/usr/local/rvm/gems/ruby-2.3.4/gems/actionpack-4.2.5/lib/action\u dispatch/middleware/templates/rescues//u trace.html.erb（2.7ms） Rendered/usr/local/rvm/gems/ruby-2.3.4/gems/actionpack-4.2.5/lib/action\u dispatch/middleware/templates/rescues//u request\u and_response.html.erb（1.2ms） rescues/layout中的Rendered/usr/local/rvm/gems/ruby-2.3.4/gems/actionpack-4.2.5/lib/action\u dispatch/middleware/templates/rescues/diagnostics.html.erb（27.9ms）

表单似乎缺少上载文件时所需的

多部分：true

。更改

表单标签

，如下所示：

<%= form_for @question, 
             url: { controller: 'questions', action: 'create'}, 
             method: :post,
             multipart: true do |f| %>

阅读Rails指南中的更多信息。

@spickermann我添加了整个错误和我所在的表单submitting@spickermann是的，是12号线，我取消了节目action@spickermann好的，我添加了表单提交时的服务器日志，这是我到目前为止得到的信息。错误解释：我唯一能想到的“以前”是您的内容类型验证。有些东西返回false并将其运行到验证中，这将导致此错误。您是否将所有验证都包含在问题中？或者您是否从

问题

模型中删除了零件？谢谢您的回答。我在表单中添加了multipart:true，但它没有删除错误。还有什么我做错的吗？

Started POST "/admin/add_question" for 10.240.1.4 at 2017-11-12 15:39:10 +0000
Cannot render console from 10.240.1.4! Allowed networks: 127.0.0.1, ::1, 127.0.0.0/127.255.255.255
Processing by QuestionsController#create as HTML
  Parameters: {"utf8"=>"✓", "authenticity_token"=>"AFcHCrw6Dthasdesh5DNgdsxmFICxxPznyXtPDtxnp8zokpyZSeRHqiGC+K4SBMHehxYBgUXra30KTCj/AxUg==", "question"=>{"subject_id"=>"39", "category_id"=>"1", "hasdiagram"=>"1", "diagram"=>#<ActionDispatch::Http::UploadedFile:0x007f8064f72100 @tempfile=#<Tempfile:/tmp/RackMultipart20171112-8403-ewq7ng.png>, @original_filename="187c38aa17afdc65ba5c1c5239219686.png", @content_type="image/png", @headers="Content-Disposition: form-data; name=\"question[diagram]\"; filename=\"187c38aa17afdc65ba5c1c5239219686.png\"\r\nContent-Type: image/png\r\n">, "question"=>"a", "option1"=>"a", "option2"=>"a", "option3"=>"a", "option4"=>"a"}, "commit"=>"Submit"}
Command :: file -b --mime '/tmp/c5769bbf6ba9051718d946344886703720171112-8403-1v5gz0n.png'
Completed 500 Internal Server Error in 13ms (ActiveRecord: 0.0ms)

NoMethodError (undefined method `before' for false:FalseClass):
  app/controllers/questions_controller.rb:11:in `create'


  Rendered /usr/local/rvm/gems/ruby-2.3.4/gems/actionpack-4.2.5/lib/action_dispatch/middleware/templates/rescues/_source.erb (6.0ms)
  Rendered /usr/local/rvm/gems/ruby-2.3.4/gems/actionpack-4.2.5/lib/action_dispatch/middleware/templates/rescues/_trace.html.erb (2.7ms)
  Rendered /usr/local/rvm/gems/ruby-2.3.4/gems/actionpack-4.2.5/lib/action_dispatch/middleware/templates/rescues/_request_and_response.html.erb (1.2ms)
  Rendered /usr/local/rvm/gems/ruby-2.3.4/gems/actionpack-4.2.5/lib/action_dispatch/middleware/templates/rescues/diagnostics.html.erb within rescues/layout (27.9ms)

<%= form_for @question, 
             url: { controller: 'questions', action: 'create'}, 
             method: :post,
             multipart: true do |f| %>