Question

我有......

/config/routes.rb ：

resources :surveys do
  resources :screenshots
end

/app/models/survey.rb ：

has_many :screenshots

/app/models/screenshot.rb ：

attr_accessible :name, :shot, :screenshot, :result_ids
belongs_to :survey
has_many :results
has_attached_file :shot, :default_url => ActionController::Base.helpers.asset_path('missing_:style.png')

/db/schema.rb ：

create_table "screenshots", :force => true do |t|
  t.integer  "survey_id"
  t.boolean  "resetting_cache",   :default => false
  t.string   "url"
  t.string   "shot_file_name"
  t.string   "shot_content_type"
  t.integer  "shot_file_size"
  t.datetime "shot_updated_at"
  t.boolean  "include",           :default => false
  t.datetime "created_at",                           :null => false
  t.datetime "updated_at",                           :null => false
  t.string   "name"
end

/app/controllers/screenshots_controller.rb ：

def new
  @survey = Survey.find(params[:survey_id])
  @competitor = @survey.competitor
  @screenshot = Screenshot.new
end

def create
  @survey = Survey.find(params[:survey_id])
  @screenshot = Screenshot.new(params[:screenshot])
  @competitor = @survey.competitor
  flash[:notice] = "Screenshot was successfully added." if @screenshot.save
  respond_with(@survey, @screenshot)
end

/app/views/screenshots/_form.html.haml ：

= simple_form_for [@survey, @screenshot] do |f|
  = f.error_notification
  = f.file_field :shot
  = f.association :results, :collection => @survey.selected_results
  = f.button :submit, :label => "Save", :id => "submit_screenshot"

有谁知道@screenshot = Screenshot.new(params[:screenshot])为什么会给我unknown attribute: screenshot错误？

此时的典型params将为：

=> {"utf8"=>"✓",
 "authenticity_token"=>"t33SO+/mpPlQY/+7+5iRTe6O2zL/MtqisYXyghzkLY8=",
 "screenshot"=>
  {"screenshot"=>
    #<ActionDispatch::Http::UploadedFile:0x007fd5cca0ace0
     @content_type="image/png",
     @headers=
      "Content-Disposition: form-data; name=\"screenshot[screenshot]\"; filename=\"youtube.png\"\r\nContent-Type: image/png\r\n",
     @original_filename="youtube.png",
     @tempfile=
      #<File:/var/folders/k9/vnpft_6d7qs6xmdb9_4svvmw0000gn/T/RackMultipart20131125-3030-1gmx1sy>>,
   "result_ids"=>["", "29857"]},
 "commit"=>"Create Screenshot",
 "action"=>"create",
 "controller"=>"screenshots",
 "survey_id"=>"14564"}

Answer 1

"screenshot"=> #<ActionDispatch::Http::UploadedFile:0x007fd5cca0ace0>

此参数应调用shot，而不是screenshot。 shot是您在模型中为附件命名的内容。

Answer 2

在屏幕截图模型的attr_accessible中，您包括：screenshot。由于这是模型的名称而不是模型中的属性，因此您无需将其包含在attr_accessible中。这可能就是把它扔掉了。

另外，你的意思是你的文件名是models / screenshot.rb，而不是模特/截图吗？

Paperclip为什么会给我这个“未知属性”错误？

2 个答案: