Question

我正在关注教程：https://www.youtube.com/watch?v=7-1HCWbu7iU 我已经使用设计宝石做了Pintrest克隆并没有问题。当我尝试将current_user添加到链接控制器时，我得到了未定义的方法current_user＆＃34;。我尝试了一切......甚至从头开始重做应用程序，定义current_user，重置数据库。我猜宝石应该自动处理这个方法，对吗？

以下是我的步骤：

1. Generate new app - rails new raddit
2. Generate scaffold: rails g scaffold link title:string url:string
3. rake db:migrate
4. add gem 'devise', '~> 3.3.0' to gem file and run bundle install
5. run rails g devise:install
6. add file to development.rb - config.action_mailer.default_url_options = { host: 'localhost', port: 3000 }
7. add alerts to layout/application.html (as per devise documentation)
8. generate view file - rails g devise:views
9. generate user - rails g devise User
10. rake db:migrate
11. rails s
12. go to localhost:3000/users/sign_up (works ok)
13. Add relation to models: user.rb - has_many :links ; link.rb -   belongs_to :user
14. Create migration: rails generate migration add_user_id_to_links user_id:integer:index
15. rake db:migrate
16. go to rails console and save assocation between user and links.
17. Add current_user to links controller - Getting undefined 'curren_user method' once I go to localhost:3000/links/new

这是我的代码：

  class LinksController < ApplicationController
  before_action :set_link, only: [:show, :edit, :update, :destroy]

  def index
     @links = Link.all
  end

  def show
  end

  def new
    @link = Link.current_user.links.build
  end

  def edit
  end

  def create
    @link = current_user.build(link_params)

    respond_to do |format|
      if @link.save
        format.html { redirect_to @link, notice: 'Link was       successfully created.' }
         format.json { render :show, status: :created, location:  @link }
      else
         format.html { render :new }
         format.json { render json: @link.errors, status: :unprocessable_entity }
      end
    end
  end


  def update
    respond_to do |format|
      if @link.update(link_params)
        format.html { redirect_to @link, notice: 'Link was successfully updated.' }
        format.json { render :show, status: :ok, location: @link }
      else
        format.html { render :edit }
        format.json { render json: @link.errors, status: :unprocessable_entity }
      end
    end
  end

  def destroy
       @link.destroy
       respond_to do |format|
       format.html { redirect_to links_url, notice: 'Link was successfully destroyed.' }
      format.json { head :no_content }
    end
  end

  private

    def set_link
      @link = Link.find(params[:id])
    end

   def link_params
      params.require(:link).permit(:title, :url)
   end
   end

我的模特：link.rb

class Link < ActiveRecord::Base
    belongs_to :user
end

我的模特：user.rb

class User < ActiveRecord::Base
  # Include default devise modules. Others available are:
  # :confirmable, :lockable, :timeoutable and :omniauthable
  devise :database_authenticatable, :registerable,
         :recoverable, :rememberable, :trackable, :validatable
  has_many :links
end

Answer 1

您正在调用Link.current_user的新操作中获取未定义的方法“current_user”。

var maxTotal = 1500; //for you 8000
        var objects = new List<Item>()
                      {
                          new Item() {Score = 10, Price = 100},
                          new Item() {Score = 20, Price = 800},
                          new Item() {Score = 40, Price = 600},
                          new Item() {Score = 5, Price = 300},
                      };

        decimal runningTotal = 0;
        var newList = objects
            .OrderByDescending(p => p.Score)
            .Select(p =>
                    {
                        runningTotal = runningTotal + p.Price;
                        return new ItemWithRunningTotal()
                               {
                                   Item = p,
                                   RunningTotal = runningTotal
                               };
                    })
            .OrderByDescending(p => p.RunningTotal)
            .Where(p => p.RunningTotal <= maxTotal).Take(15);

应该是

def new
  @link = Link.current_user.links.build
end

链接没有current_user方法，这就是问题所在。 current_user在控制器的上下文中定义，应该像在create操作中一样使用。

Answer 2

应该是

@link = current_user.links.build

采取新行动

如果您遇到的问题不仅仅是在新操作中输入exit并检查控制台中的current_user ..您可以从控制台获取错误..所以每次都要检查您的控制台。

使用better_errors gem ..了解有关特定错误的更多信息

在使用devise gem时获取current_user未定义的方法 - Ruby on Rails 4.1.5

2 个答案: