的Rails：根據路線

Question

我在尋找解決以下情況最好的做法不同的控制器行爲：

我有一種「添加劑」型號應與一些多到許多相關的其他型號。

例子：

# Meal-Model 
has_and_belongs_to_many :additives 

# Offer-Model 
has_and_belongs_to_many :additives 

# Additive-Model 
has_and_belongs_to_many :meals 
has_and_belongs_to_many :meals 

的路由嵌套在以下方式：

resources :offers do 
    resources :additives 
end 
resources :meals do 
    resources :additives 
end 

所以我得到的網址是這樣的：

/offers/123/additives 
/meals/567/additives 

兩種途徑都導致同一控制器行動，這是additives#index。在添加劑控制器中，我檢查是否有參數可供選擇要提取哪些數據：

class AdditivesController < ApplicationController 

before_filter :offermealswitch 

# GET /restaurants/1/meals/123/additives 
# GET /restaurants/1/offers/123/additives 
def index 
    @additives = @additivemeal.additives  
end 

def offermealswitch 
    if params.has_key?(:meal_id) 
    @additivemeal = Meal.find(params[:meal_id]) 
    @type = "Meal" 
    elsif params.has_key?(:offer_id) 
    @additivemeal = Offer.find(params[:offer_id]) 
    @type = "Offer" 
    end 
end 

end 

這是處理該問題的正確方法嗎？它工作得很好，但我不舒服這是軌道的方式... 感謝您的答案！

Answer 1

嘆息切換接聽空間，所以我至少可以加回車和使代碼不是啞巴。

我同意fl00r的答案，但想補充一點，你需要這樣來實例化對象：

@type = params[:type] 
@obj = @type.constantize.find(params["#{type}_id"]) 
@additives = @obj.additives 

Answer 2

編輯相對於@Taryn東

resources :offers do 
    resources :additives, :type => "Offer" 
end 
resources :meals do 
    resources :additives, :type => "Meal" 
end 

class AdditivesController < ApplicationController 
    before_filter :find_additive 

    def index 
    @additives = @additive.additives  
    end 

    private 
    def find_additive 
    @type = params[:type] 
    @additive = @type.constantize.find([@type, "id"].join("_")) # or "#{@type}_id", as you wish 
    end 
end