图片上传中未定义的方法`<<`

Question

def create
    @product = Product.find(1)
    @product.images << params[:image]
    @product.save
end

架构是

 t.string   "images",       default: [],              array: true

如果图像已经存在，我希望将参数中的图像分配给图像数组。新图像应该附加，否则它应该是第一个

这是产品型号

class Product < ActiveRecord::Base
    mount_uploader  :images, ProductUploader

    validates :name, presence: true 
    validates :price, presence: true
    validates :availability, presence: true
    validates :about, presence: true
    validates :ref, presence: true
    validates :texture, presence: true
    validates :shipping, presence: true
    validates :category, presence: true
    validates :notes, presence: true

end

我通过 carrierwave uploader 命令生成了 ProductUploader

class ProductUploader < CarrierWave::Uploader::Base

  # Include RMagick or MiniMagick support:
  # include CarrierWave::RMagick
  # include CarrierWave::MiniMagick

  # Choose what kind of storage to use for this uploader:
  storage :file
  # storage :fog

  # Override the directory where uploaded files will be stored.
  # This is a sensible default for uploaders that are meant to be mounted:
  def store_dir
    "uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
  end

  # Provide a default URL as a default if there hasn't been a file uploaded:
  # def default_url
  #   # For Rails 3.1+ asset pipeline compatibility:
  #   # ActionController::Base.helpers.asset_path("fallback/" + [version_name, "default.png"].compact.join('_'))
  #
  #   "/images/fallback/" + [version_name, "default.png"].compact.join('_')
  # end

  # Process files as they are uploaded:
  # process scale: [200, 300]
  #
  # def scale(width, height)
  #   # do something
  # end

  # Create different versions of your uploaded files:
  # version :thumb do
  #   process resize_to_fit: [50, 50]
  # end

  # Add a white list of extensions which are allowed to be uploaded.
  # For images you might use something like this:
  # def extension_whitelist
  #   %w(jpg jpeg gif png)
  # end

  # Override the filename of the uploaded files:
  # Avoid using model.id or version_name here, see uploader/store.rb for details.
  # def filename
  #   "something.jpg" if original_filename
  # end

end

上传图片后，图片显示在参数中。但不会保存在 table 中。这是 byebug

的截图

编辑：

我进步了

对于这样的图像，我将字符串 [] 更新为 json

它不是以字符串形式出现的文件，而是以文件形式出现的。现在唯一的问题是，我无法在参数

中正确访问名称 name=\"image[avatar_1]\"

"utf8"=>"✓", "authenticity_token"=>"JbtcVdUvPJIzSHycX0wdr349zcATDN51vSewI33nvHIKQdhxxgxWUEJz9ZsubNrgvq2ftO+DosHXWM8Tipce7w==", "image"=>{"avatar_1"=>#<ActionDispatch::Http::UploadedFile:0x007f2ba8377f78 @tempfile=#<Tempfile:/tmp/RackMultipart20160704-20497-1czlw3s.png>, @original_filename="no-save.png", @content_type="image/png", @headers="Content-Disposition: form-data; name=\"image[avatar_1]\"; filename=\"no-save.png\"\r\nContent-Type: image/png\r\n">}, "commit"=>"submit", "controller"=>"upload", "action"=>"create"}

这是视图文件

<%= simple_form_for :image, method: :post, url: save_image_path do |f| %>

        <%= f.file_field :avatar_1 %>

        <%= f.submit :submit %>

    <% end %>

这里是 avatar_1。我需要在创建代码中更改它，但我没有正确访问参数本身

Answer 1

让我们把你的问题分成子问题：

数据库和控制器

您的数据库和控制器工作正常。无需更改任何内容！

上传的图片

您上传的图片（在 params[:image] 中）是 String，而不是 ActionDispatch::Http::UploadedFile。您可能应该将 multipart form data 添加到您的表单中。

更改文件名

您可以使用params[:image].original_filename访问上传的文件名。如果你想更改文件名，那么你可以为你的 CarrierWave 处理程序（最后一个，已注释）重新定义 filename 方法。

图片上传中未定义的方法`<<`

Undefined method `<<` in image upload

ruby-on-rails

carrierwave

数据库和控制器

上传的图片

更改文件名