Ruby on rails 3 CarrierWave显示图像\u url错误

我正在使用CarrierWave将图像上载到我的服务器。然而，当我用image\u url引用它们时，我得到了nil的NoMethodError:NilClass，用于

image\u url

app/assets/views/albums/index.html.erb

<% @albums.each do |album| %>
....
<div>
    <%= image_tag @album.image_url.to_s %>
</div>
<%end%>

namespace :admin do
    root :to => "dashboard#index"
    resources :dashboard
    resources :albums do
        resources :images
end
    get "admin/album"

<div>
    <%= f.file_field :image %>
</div>

class Image < ActiveRecord::Base
    attr_accessible :album_id, :title, :image
    belongs_to :album
    mount_uploader :image, ImageUploader
end

 # encoding: utf-8

class ImageUploader < CarrierWave::Uploader::Base

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

  # Include the Sprockets helpers for Rails 3.1+ asset pipeline compatibility:
  # include Sprockets::Helpers::RailsHelper
  # include Sprockets::Helpers::IsolatedHelper

  # 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:
  #   # 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 :scale => [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_white_list
  #   %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

 <h1>These are the albums</h1>
 <% @albums.each do |album| %>
 <div class="item" style="background: #e4e4e4; border: 2px solid #c9c9c9; padding:1.5em  0 1.5em 0; width:17em; font-family: 'Signika Negative';">
 <div class="title" style="background: #d3d3d3; display: inline-block; padding:1.5em 0      1.5em 1em; width: 12em;">
<strong>Title</strong> </br>
<%= album.title %></div>
 </br>
 <div class="description" style="background: #f9f9f9; display: inline-block; padding: 1.5em 0 1.5em 1em; width: 12em;">
<strong>Description</strong> </br>
<%= album.description %>
 </div>
</br>
<div>
<%= image_tag album.image.image_url.to_s %>
</div>
<div>

</div>
<%= link_to "Delete", admin_album_path(album), :method => :delete, :style => "margin: 1em 0 0 1em; display: block;" %>
</br>
</div>
<% end %>
<%=link_to "New Album", :controller => "albums", :action => "new" %>
<%=link_to "Manage Pictures"%>

app/assets/views/albums/new.html.erb

<% @albums.each do |album| %>
....
<div>
    <%= image_tag @album.image_url.to_s %>
</div>
<%end%>

namespace :admin do
    root :to => "dashboard#index"
    resources :dashboard
    resources :albums do
        resources :images
end
    get "admin/album"

<div>
    <%= f.file_field :image %>
</div>

class Image < ActiveRecord::Base
    attr_accessible :album_id, :title, :image
    belongs_to :album
    mount_uploader :image, ImageUploader
end

 # encoding: utf-8

class ImageUploader < CarrierWave::Uploader::Base

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

  # Include the Sprockets helpers for Rails 3.1+ asset pipeline compatibility:
  # include Sprockets::Helpers::RailsHelper
  # include Sprockets::Helpers::IsolatedHelper

  # 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:
  #   # 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 :scale => [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_white_list
  #   %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

 <h1>These are the albums</h1>
 <% @albums.each do |album| %>
 <div class="item" style="background: #e4e4e4; border: 2px solid #c9c9c9; padding:1.5em  0 1.5em 0; width:17em; font-family: 'Signika Negative';">
 <div class="title" style="background: #d3d3d3; display: inline-block; padding:1.5em 0      1.5em 1em; width: 12em;">
<strong>Title</strong> </br>
<%= album.title %></div>
 </br>
 <div class="description" style="background: #f9f9f9; display: inline-block; padding: 1.5em 0 1.5em 1em; width: 12em;">
<strong>Description</strong> </br>
<%= album.description %>
 </div>
</br>
<div>
<%= image_tag album.image.image_url.to_s %>
</div>
<div>

</div>
<%= link_to "Delete", admin_album_path(album), :method => :delete, :style => "margin: 1em 0 0 1em; display: block;" %>
</br>
</div>
<% end %>
<%=link_to "New Album", :controller => "albums", :action => "new" %>
<%=link_to "Manage Pictures"%>

app/assets/views/albums/index.html.erb

<% @albums.each do |album| %>
....
<div>
    <%= image_tag @album.image_url.to_s %>
</div>
<%end%>

namespace :admin do
    root :to => "dashboard#index"
    resources :dashboard
    resources :albums do
        resources :images
end
    get "admin/album"

<div>
    <%= f.file_field :image %>
</div>

class Image < ActiveRecord::Base
    attr_accessible :album_id, :title, :image
    belongs_to :album
    mount_uploader :image, ImageUploader
end

 # encoding: utf-8

class ImageUploader < CarrierWave::Uploader::Base

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

  # Include the Sprockets helpers for Rails 3.1+ asset pipeline compatibility:
  # include Sprockets::Helpers::RailsHelper
  # include Sprockets::Helpers::IsolatedHelper

  # 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:
  #   # 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 :scale => [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_white_list
  #   %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

 <h1>These are the albums</h1>
 <% @albums.each do |album| %>
 <div class="item" style="background: #e4e4e4; border: 2px solid #c9c9c9; padding:1.5em  0 1.5em 0; width:17em; font-family: 'Signika Negative';">
 <div class="title" style="background: #d3d3d3; display: inline-block; padding:1.5em 0      1.5em 1em; width: 12em;">
<strong>Title</strong> </br>
<%= album.title %></div>
 </br>
 <div class="description" style="background: #f9f9f9; display: inline-block; padding: 1.5em 0 1.5em 1em; width: 12em;">
<strong>Description</strong> </br>
<%= album.description %>
 </div>
</br>
<div>
<%= image_tag album.image.image_url.to_s %>
</div>
<div>

</div>
<%= link_to "Delete", admin_album_path(album), :method => :delete, :style => "margin: 1em 0 0 1em; display: block;" %>
</br>
</div>
<% end %>
<%=link_to "New Album", :controller => "albums", :action => "new" %>
<%=link_to "Manage Pictures"%>

这些是相册
标题



说明



：delete，：style=>“页边距：1em 0 0 1em；显示：块；”%>


“相册”，：操作=>“新”%>

你似乎与相册和图像有着某种联系。假设相册中有许多您需要的图像：

@albums.each do |album|
  album.images.each{|image| image.image_url }
end

---

它不应该是普通的相册.image.image\u url而不是相册.image\u url还是同样的错误。我试过很多东西。。。我很困惑。你确定相册。图片给你什么，做这个时会出现什么错误吗？是的，我可以确认这是完全相同的错误

nil:NilClass的未定义方法“image\u url”两次都是。什么是
album.image
give-uthis清除了错误，但它仍然没有链接到图像，只是
/assets
上载的图像实际上是公开/上载的吗？您可能需要查看视图以确保正确上载图像。查看此处以构建用于上载图像的嵌套表单：