Ruby on rails 3.2 Rails属于关联在视图中返回nil
我是ruby和rails的新手,已经为这个问题挣扎了几天。我已经在寻找答案,但找不到解决办法 我在游戏、票务和玩家之间建立了一种多对多的联系,这种联系是通过协会实现的。相关的关联声明可以如下所示:Ruby on rails 3.2 Rails属于关联在视图中返回nil,ruby-on-rails-3.2,Ruby On Rails 3.2,我是ruby和rails的新手,已经为这个问题挣扎了几天。我已经在寻找答案,但找不到解决办法 我在游戏、票务和玩家之间建立了一种多对多的联系,这种联系是通过协会实现的。相关的关联声明可以如下所示: class Game < ActiveRecord::Base has_many :tickers, :dependent => :destroy has_many :players, :through => :tickers end class T
class Game < ActiveRecord::Base
has_many :tickers, :dependent => :destroy
has_many :players, :through => :tickers
end
class Ticker < ActiveRecord::Base
belongs_to :games
belongs_to :players
end
class Player < ActiveRecord::Base
has_many :tickers, :dependent => :destroy
has_many :games, :through => :tickers
end
我的数据库架构:
create_table "games", :force => true do |t|
t.datetime "created_at", :null => false
t.datetime "updated_at", :null => false
end
create_table "players", :force => true do |t|
t.string "player_name"
t.datetime "created_at", :null => false
t.datetime "updated_at", :null => false
end
create_table "tickers", :force => true do |t|
t.integer "activity_id"
t.integer "player_id"
t.integer "time"
t.datetime "created_at", :null => false
t.datetime "updated_at", :null => false
t.integer "game_id"
end
以下是我如何创建一个新的ticker实例(目前):
app/views/games/show.html.erb:
<p id="notice"><%= notice %></p>
<p>
<b>Home:</b>
<%= @game.home_team.team_name %>
</p>
<p>
<b>Away:</b>
<%= @game.away_team.team_name %>
</p>
<table>
<tr>
<th>Activity</th>
<th>Player</th>
<th>Time</th>
<th></th>
<th></th>
<th></th>
</tr>
<% @tickers.each do |ticker| %>
<tr>
<td><%= ticker.activity_id %></td>
<td><%= ticker.players.player_name %></td>
<td><%= ticker.time %></td>
<td><%= link_to 'Show', ticker %></td>
<td><%= link_to 'Edit', edit_ticker_path(ticker) %></td>
<td><%= link_to 'Destroy', ticker, confirm: 'Are you sure?', method: :delete %> </td>
</tr>
<% end %>
</table>
<%= link_to 'New Ticker', new_ticker_path(:game_id=>@game.id) %>
所属的应为单数。即
belongs_to :game #u have specified 'games'
所属的应为单数。即
belongs_to :game #u have specified 'games'
是 啊就这样。但你能给我解释一下,为什么它是单数的,而在另一种情况下是复数的?因为一个物体总是属于“一个”父母而不是许多父母,并且有“一个或多个”孩子。如果你仍然希望现有代码正常工作,那么你可以在类中添加名为“games”和“players”的方法,并使用它们的id获取“parent”,但从长远来看这没有意义。我无法升级投票。“投票需要15个声望”——我没有:(是的。就是这样。但你能解释一下,为什么它是单数的,在另一种情况下是复数的吗?因为一个对象总是属于“一个”父对象,而不是多个,并且有“一个或多个”子对象。如果你仍然希望现有代码正常工作,那么你可以在类中添加名为“games”和“players”的方法,并使用它们的id获取“父对象”,但不需要从长远来看是没有意义的。我不能提高投票率。“提高投票率需要15个声誉”-我没有-:(
create_table "games", :force => true do |t|
t.datetime "created_at", :null => false
t.datetime "updated_at", :null => false
end
create_table "players", :force => true do |t|
t.string "player_name"
t.datetime "created_at", :null => false
t.datetime "updated_at", :null => false
end
create_table "tickers", :force => true do |t|
t.integer "activity_id"
t.integer "player_id"
t.integer "time"
t.datetime "created_at", :null => false
t.datetime "updated_at", :null => false
t.integer "game_id"
end
<%= link_to 'New Ticker', new_ticker_path(:game_id=>@game.id) %>
<%= form_for(@ticker) do |f| %>
<% if @ticker.errors.any? %>
<div id="error_explanation">
<h2><%= pluralize(@ticker.errors.count, "error") %> prohibited this ticker from being saved:</h2>
<ul>
<% @ticker.errors.full_messages.each do |msg| %>
<li><%= msg %></li>
<% end %>
</ul>
</div>
<% end %>
<div class="field">
<%= f.hidden_field :game_id, :value => params[:game_id] %>
</div>
<div class="field">
<%= f.label :activity_id %><br />
<%= f.number_field :activity_id %>
</div>
<div class="field">
<%= f.label :player_id %><br />
<%= f.number_field :player_id %>
</div>
<div class="field">
<%= f.label :time %><br />
<%= f.number_field :time %>
</div>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
def new
@ticker = Ticker.new
respond_to do |format|
format.html # new.html.erb
format.json { render json: @ticker }
end
end
def create
@ticker = Ticker.new(params[:ticker])
respond_to do |format|
if @ticker.save
format.html { redirect_to @ticker, notice: 'Ticker was successfully created.' }
format.json { render json: @ticker, status: :created, location: @ticker }
else
format.html { render action: "new" }
format.json { render json: @ticker.errors, status: :unprocessable_entity }
end
end
end
belongs_to :game #u have specified 'games'