的Rails：根据路线

Question

我在寻找解决以下情况最好的做法不同的控制器行为：

我有一种“添加剂”型号应与一些多到许多相关的其他型号。

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 

所以我得到的网址是这样的：

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

两种途径都导致同一控制器行动，这是additives#index。在添加剂控制器中，我检查是否有参数可供选择要提取哪些数据：

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 

这是处理该问题的正确方法吗？它工作得很好，但我不舒服这是轨道的方式... 感谢您的答案！

Answer 1

叹息切换接听空间，所以我至少可以加回车和使代码不是哑巴。

我同意fl00r的答案，但想补充一点，你需要这样来实例化对象：

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

Answer 2

编辑相对于@Taryn东

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