NoMethodError，has_many和belongs_to关联

Question

我收到以下错误。

NoMethodError in Users#show
...
undefined method 'contents' for #    <Article::ActiveRecord_Associations_CollectionProxy:0x43745a0>
...
<div class="col-md-6" style="background:yellow;"><%= @User.articles.contents %></div>

user.rb

class User < ActiveRecord::Base
    has_many :articles
end

article.rb

class Article < ActiveRecord::Base
    belongs_to :user
end

users_controller.rb

class UsersController < ApplicationController
  def index
  ...
  end
  def show
    @user = User.find(params[:id])
    ...
  end

end

\\用户\\ show.html.erb

  <div class="row">
    <div class="col-md-12" style="background:orange;"><%= @user.title %></div>
  </div>
  <div class="row">
    <div class="col-md-6" style="background:blue;"><%= @user.articles.count %></div>
    <div class="col-md-6" style="background:yellow;"><%= @user.articles.contents %></div>
  </div>

添加了以下内容：

DB \\ schema.rb

ActiveRecord::Schema.define(version: 20150720033506) do

  create_table "articles", force: true do |t|
    t.integer  "user_id"
    t.integer  "day"
    ...
    t.string   "title"
    t.string   "contents"
    ...
  end

  create_table "users", force: true do |t|
    t.date     "user_date"
    t.string   "title"
    t.datetime "created_at"
    t.datetime "updated_at"
  end

请告诉我如何避免此错误。 先感谢您。

Answer 1

问题是您要在文章集合上调用contents方法。

尝试这个：

<div class="col-md-6" style="background:yellow;"><%= @user.articles.map(&:contents).join(', ') %></div>