Rails无法将字符串转换为整数错误

Question

我正在使用回形针，并且已将多个文件上传添加到一个模型中。 一切正常，除非我尝试更新新文件。 它引发此错误：

can't convert String into Integer
app/controllers/listings_controller.rb:86:in `block in update'
app/controllers/listings_controller.rb:85:in `update'

如何解决此问题，以便可以更新新文件？ 提前致谢。

asset.rb

class Asset < ActiveRecord::Base

  belongs_to :member
  belongs_to :listing

  attr_accessible :asset

  has_attached_file :asset, styles: { large: "700x700>", thumb: "100x100#" }

  validates_attachment_size :asset, :less_than_or_equal_to=>10.megabyte
  validates_attachment_content_type :asset, :content_type=>['image/jpeg', 'image/jpg', 'image/png', 'image/gif']

end

listing.rb

has_many :assets, :dependent => :destroy
accepts_nested_attributes_for :assets, :allow_destroy => true

attr_accessible :assets_attributes

列表/ _edit_form.html.erb

<%= simple_form_for(@listing, :html => { class: 'form-horizontal ', :multipart => true }) do |f| %>
  <% if @listing.errors.any? %>
    <%= f.error_notification %>

    <div>
        <%= file_field_tag('listing_assets_asset', multiple: true, name: "listing[assets_attributes][][asset]", id: 'file-upload3', class: '') %>
    </div>

<% end %>

listings_controller.rb

  before_filter :authenticate_member!, only: [:new, :create, :edit, :update, :destroy] 
  before_filter :find_member
  before_filter :find_listing, only: [:edit, :update, :destroy]

  def new
    @listing = Listing.new

    respond_to do |format|
      format.html # new.html.erb
      format.json { render json: @listing }
    end
  end

  # GET /listings/1/edit
  def edit

  end

  # POST /listings
  # POST /listings.json
  def create
    @listing = current_member.listings.new(params[:listing])

    respond_to do |format|
      if @listing.save
        current_member.create_activity(@listing, 'created')
        format.html { redirect_to @listing }
        format.json { render json: @listing, status: :created, location: @listing }
      else
        format.html { render action: "new" }
        format.json { render json: @listing.errors, status: :unprocessable_entity }
      end
    end
  end

  # PUT /listings/1
  # PUT /listings/1.json
  def update

    respond_to do |format|
      if @listing.update_attributes(params[:listing])
        format.html { redirect_to @listing }
        format.json { head :no_content }
      else
        format.html { render action: "edit" }
        format.json { render json: @listing.errors, status: :unprocessable_entity }
      end
    end
  end

  private

    def find_member
      @member = Member.find_by_user_name(params[:user_name])
    end 

    def find_listing
      @listing = current_member.listings.find(params[:id])
    end

参数

{"utf8"=>"✓",
 "_method"=>"put",
 "authenticity_token"=>"ilfHooJlfqXqEoHyB6GD6uoXG33Vqs6eliIec6tToXo=",
 "listing"=>{"title"=>"Testing inputs",
 "assets_attributes"=>{"asset"=>[#<ActionDispatch::Http::UploadedFile:0x777a788 @original_filename="0002k2qr.jpeg",
 @content_type="image/jpeg",
 @headers="Content-Disposition: form-data; name=\"listing[assets_attributes][asset][]\"; filename=\"0002k2qr.jpeg\"\r\nContent-Type: image/jpeg\r\n",
 @tempfile=#<File:C:/Users/owner/AppData/Local/Temp/RackMultipart20150320-7872-1hju1df>>,
 #<ActionDispatch::Http::UploadedFile:0x777a1a0 @original_filename="2Pac FtNotorious BIG NotoriousBIGandTupacShakur.jpg",
 @content_type="image/jpeg",
 @headers="Content-Disposition: form-data; name=\"listing[assets_attributes][asset][]\"; filename=\"2Pac+FtNotorious+BIG+NotoriousBIGandTupacShakur.jpg\"\r\nContent-Type: image/jpeg\r\n",
 @tempfile=#<File:C:/Users/owner/AppData/Local/Temp/RackMultipart20150320-7872-re8hr6>>],
 "0"=>{"_destroy"=>"0",
 "id"=>"29"},
 "1"=>{"_destroy"=>"0",
 "id"=>"30"},
 "2"=>{"_destroy"=>"0",
 "id"=>"31"},
 "3"=>{"_destroy"=>"0",
 "id"=>"32"},
 "4"=>{"_destroy"=>"0",
 "id"=>"33"},
 "5"=>{"_destroy"=>"0",
 "id"=>"35"}},
 "category"=>"Music",
 "description"=>""},
 "commit"=>"Update Listing",
 "id"=>"16-testing-inputs"}

development.log

Started PUT "/market/listings/16-testing-inputs" for 127.0.0.1 at 2015-03-20 22:11:58 -0700
Processing by ListingsController#update as HTML
  Parameters: {"utf8"=>"✓", "authenticity_token"=>"ilfHooJlfqXqEoHyB6GD6uoXG33Vqs6eliIec6tToXo=", "listing"=>{"title"=>"Testing inputs", "assets_attributes"=>{"asset"=>[#<ActionDispatch::Http::UploadedFile:0x777a788 @original_filename="0002k2qr.jpeg", @content_type="image/jpeg", @headers="Content-Disposition: form-data; name=\"listing[assets_attributes][asset][]\"; filename=\"0002k2qr.jpeg\"\r\nContent-Type: image/jpeg\r\n", @tempfile=#<File:C:/Users/owner/AppData/Local/Temp/RackMultipart20150320-7872-1hju1df>>, #<ActionDispatch::Http::UploadedFile:0x777a1a0 @original_filename="2Pac FtNotorious BIG NotoriousBIGandTupacShakur.jpg", @content_type="image/jpeg", @headers="Content-Disposition: form-data; name=\"listing[assets_attributes][asset][]\"; filename=\"2Pac+FtNotorious+BIG+NotoriousBIGandTupacShakur.jpg\"\r\nContent-Type: image/jpeg\r\n", @tempfile=#<File:C:/Users/owner/AppData/Local/Temp/RackMultipart20150320-7872-re8hr6>>], "0"=>{"_destroy"=>"0", "id"=>"29"}, "1"=>{"_destroy"=>"0", "id"=>"30"}, "2"=>{"_destroy"=>"0", "id"=>"31"}, "3"=>{"_destroy"=>"0", "id"=>"32"}, "4"=>{"_destroy"=>"0", "id"=>"33"}, "5"=>{"_destroy"=>"0", "id"=>"35"}},  "description"=>""}, "commit"=>"Update Listing", "id"=>"16-testing-inputs"}
  [1m[35mMember Load (0.0ms)[0m  SELECT "members".* FROM "members" WHERE "members"."id" = 1 LIMIT 1
  [1m[36mMember Load (1.0ms)[0m  [1mSELECT "members".* FROM "members" WHERE "members"."user_name" IS NULL LIMIT 1[0m
  [1m[35mListing Load (0.0ms)[0m  SELECT "listings".* FROM "listings" WHERE "listings"."member_id" = 1 AND "listings"."id" = ? LIMIT 1  [["id", "16-testing-inputs"]]
  [1m[36m (0.0ms)[0m  [1mbegin transaction[0m
  [1m[36m (0.0ms)[0m  [1mrollback transaction[0m
Completed 500 Internal Server Error in 51ms

TypeError (can't convert String into Integer):
  app/controllers/listings_controller.rb:86:in `block in update'
  app/controllers/listings_controller.rb:85:in `update'

Answer 1

通过查看本文，我找到了解决问题的方法： http : //www.railscook.com/recipes/multiple-files-upload-with-nested-resource-using-paperclip-in-rails/

我需要更改处理多个上传文件的方式。

将我的输入更改为此：

<%= file_field_tag "assets[]", type: :file, multiple: true, id: 'file-upload3' %>

并将以下内容添加到我的控制器中的创建和更新操作中：

if params[:assets]
    params[:assets].each { |asset|
      @listing.assets.create(asset: asset)
    }
end

做这些事情解决了我的问题。