1

以下是我对 Devise 辅助方法 current_user 的用户的理解：

  1. 它仅可用于控制器和视图，但不能用于建模。

  2. 它是当前登录用户的用户对象。

那么，如果 user_signed_in? 那么我应该能够做诸如 current_user.email、current_user.id 之类的事情（我在 User 对象中有 email 和 id）。问题是我得到

undefined method '[]' for nil:NilClass

当我使用 current_user.email

我可能会忘记什么？

完整跟踪：

undefined method '[]' for nil:NilClass

Extracted source (around line #12):

9:           <% if user_signed_in? %>
10:               <li class="right_line"><%= link_to(SIGN_OUT_TITLE, destroy_user_session_path, :method => :delete) %></li>
11:               <li><%= link_to "Update user info", edit_user_path(current_user) %></li>
12:               <% if !user_registered(current_user.email) %>
13:                 <%= link_to "Register", register_path(current_user.id)  %>
14:               <% end %>
15:           <% else %

Trace of template inclusion: app/views/layouts/application.html.erb

Rails.root: /Users/mine/Documents/projects/rails/registrar
Application Trace | Framework Trace | Full Trace

lib/assets/common_lib.rb:355:in 'user_registered'
app/views/layouts/_header.html.erb:12:in '_app_views_layouts__header_html_erb__1686513977508462374_70171327747820'
actionpack (3.2.12) lib/action_view/template.rb:145:in 'block in render'
activesupport (3.2.12) lib/active_support/notifications.rb:125:in 'instrument'
actionpack (3.2.12) lib/action_view/template.rb:143:in 'render'
actionpack (3.2.12) lib/action_view/renderer/partial_renderer.rb:265:in 'render_partial'
actionpack (3.2.12) lib/action_view/renderer/partial_renderer.rb:238:in 'block in render'
actionpack (3.2.12) lib/action_view/renderer/abstract_renderer.rb:38:in 'block in instrument'
activesupport (3.2.12) lib/active_support/notifications.rb:123:in 'block in instrument'
activesupport (3.2.12) lib/active_support/notifications/instrumenter.rb:20:in 'instrument'
activesupport (3.2.12) lib/active_support/notifications.rb:123:in 'instrument'
actionpack (3.2.12) lib/action_view/renderer/abstract_renderer.rb:38:in 'instrument'
actionpack (3.2.12) lib/action_view/renderer/partial_renderer.rb:237:in 'render'
actionpack (3.2.12) lib/action_view/renderer/renderer.rb:41:in 'render_partial'
actionpack (3.2.12) lib/action_view/helpers/rendering_helper.rb:27:in 'render'
app/views/layouts/application.html.erb:18:in '_app_views_layouts_application_html_erb__756280269371614523_70171335312940'
actionpack (3.2.12) lib/action_view/template.rb:145:in 'block in render'
activesupport (3.2.12) lib/active_support/notifications.rb:125:in 'instrument'
actionpack (3.2.12) lib/action_view/template.rb:143:in 'render'
actionpack (3.2.12) lib/action_view/renderer/template_renderer.rb:59:in 'render_with_layout'
actionpack (3.2.12) lib/action_view/renderer/template_renderer.rb:45:in 'render_template'
actionpack (3.2.12) lib/action_view/renderer/template_renderer.rb:18:in 'render'
actionpack (3.2.12) lib/action_view/renderer/renderer.rb:36:in 'render_template'
actionpack (3.2.12) lib/action_view/renderer/renderer.rb:17:in 'render'
actionpack (3.2.12) lib/abstract_controller/rendering.rb:110:in '_render_template'
actionpack (3.2.12) lib/action_controller/metal/streaming.rb:225:in '_render_template'
actionpack (3.2.12) lib/abstract_controller/rendering.rb:103:in 'render_to_body'
actionpack (3.2.12) lib/action_controller/metal/renderers.rb:28:in 'render_to_body'
actionpack (3.2.12) lib/action_controller/metal/compatibility.rb:50:in 'render_to_body'
actionpack (3.2.12) lib/abstract_controller/rendering.rb:88:in 'render'
actionpack (3.2.12) lib/action_controller/metal/rendering.rb:16:in 'render'
actionpack (3.2.12) lib/action_controller/metal/instrumentation.rb:40:in 'block (2 levels) in render'
activesupport (3.2.12) lib/active_support/core_ext/benchmark.rb:5:in 'block in ms'
/Users/mine/.rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/benchmark.rb:296:in 'realtime'
activesupport (3.2.12) lib/active_support/core_ext/benchmark.rb:5:in 'ms'
actionpack (3.2.12) lib/action_controller/metal/instrumentation.rb:40:in 'block in render'
actionpack (3.2.12) lib/action_controller/metal/instrumentation.rb:83:in 'cleanup_view_runtime'
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actionpack (3.2.12) lib/action_controller/metal/instrumentation.rb:39:in 'render'
actionpack (3.2.12) lib/action_controller/metal/implicit_render.rb:10:in 'default_render'
actionpack (3.2.12) lib/action_controller/metal/implicit_render.rb:5:in 'send_action'
actionpack (3.2.12) lib/abstract_controller/base.rb:167:in 'process_action'
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actionpack (3.2.12) lib/abstract_controller/callbacks.rb:18:in 'block in process_action'
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activesupport (3.2.12) lib/active_support/callbacks.rb:405:in '__run_callback'
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activesupport (3.2.12) lib/active_support/callbacks.rb:81:in 'run_callbacks'
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rack (1.4.5) lib/rack/runtime.rb:17:in 'call'
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rack (1.4.5) lib/rack/lock.rb:15:in 'call'
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railties (3.2.12) lib/rails/engine.rb:479:in 'call'
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rack (1.4.5) lib/rack/content_length.rb:14:in 'call'
railties (3.2.12) lib/rails/rack/log_tailer.rb:17:in 'call'
rack (1.4.5) lib/rack/handler/webrick.rb:59:in 'service'
/Users/mine/.rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/webrick/httpserver.rb:138:in 'service'
/Users/mine/.rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/webrick/httpserver.rb:94:in 'run'
/Users/mine/.rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/webrick/server.rb:295:in 'block in start_thread'
4

1 回答 1

0

这应该可行，我看到的唯一会导致此错误的是，您为用户使用了不同的模型名称，您的用户模型类看起来像这样：

class User < ActiveRecord::Base

  # Include default devise modules. Others available are:
  # :token_authenticatable, :confirmable,
  # :lockable, :timeoutable and :omniauthable
  devise :database_authenticatable, :registerable,
         :recoverable, :rememberable, :trackable, :validatable

  # Setup accessible (or protected) attributes for your model
  attr_accessible :email, :password, :password_confirmation, :remember_me,
                  :cellphone, :address, :name, :lastname, :nit, :phone, 
                  :verified, :level, :utype, :ustores, :image

  validates_presence_of :name

  has_many :products

end
于 2013-07-05T18:36:46.883 回答