Question

我正在尝试让订阅者通过删除表单取消订阅，然后他们输入电子邮件，然后提交然后删除订阅。不知道为什么这不起作用。我通过我的控制器尝试了很多东西。会喜欢一些建议或替代方案。

目前收到此错误

Couldn't find Subscription without an ID

订阅控制器

def destroy
    @subscriptions = Subscription.all
    @subscription = @subscriptions.find(params[:id])
    if @subscription.email == params[:email]
    @subscription.destroy
            flash[:notice] = "You have been unsubscribed"
            redirect_to root_path
        else
    end
end

路线

 Rails.application.routes.draw do
 get 'password_resets/new'

  get 'password_resets/edit'

  get 'sessions/new'

  get 'users/new'

  resources :posts
  root 'static_pages#new_home'

  resources :subscriptions, only: [:new, :create, :edit, :update, :show, :destroy]

  get '/home' =>  'static_pages#home'
  get 'subscriptions' => 'subscriptions#show'
  delete 'subscriptions' => 'subscriptions#destroy'
  get '/about' => 'static_pages#about'
  get '/author' => 'static_pages#author'
  get '/contact' => 'static_pages#contact'
  get '/book' => 'static_pages#book'
  get '/signup' => 'users#new'
  get 'login' => 'sessions#new'
  post 'login' => 'sessions#create'
  delete 'logout' => 'sessions#destroy'

  resources :users
  resources :account_activations, only: [:edit]
  resources :password_resets, only: [:new, :create, :edit, :update]

  resources :posts do
    resources :comments
  end
end

取消订阅订阅视图中的部分

<%= form_for @subscription, method: :delete do |f| %>


<div class="row">
    <h2>Unsubscribe</h2>
</div>
<div class="row newsletter">
    <form method="post" action="#" class="contact-form">
        <div class="row email-label">
        <%= f.label :email, :class => 'label-email' %>
        <%= f.email_field :email %>
        </div>
        <div class="row">
        <%= f.submit 'Unsubscribe', :class => 'btn-full-subscribe' %>
      </div>
    </form>
</center
<% end %>

我尝试了许多没有运气的事情。帮助将不胜感激。谢谢。订阅与用户模型无关。

Answer 1

此行@subscription = @subscriptions.find(params[:email])导致此问题。

尝试@subscription = @subscriptions.find_by_email(params[:email])或更好，请使用ID @subscription = @subscriptions.find(params[:id])。

ActiveRecord::find仅使用ID：http://api.rubyonrails.org/classes/ActiveRecord/FinderMethods.html#method-i-find。

Answer 2

问题在这里

@subscription = @subscriptions.find(params[:email])

因为如果您想要通过任何其他字段提取，则使用ID来获取记录find_by_"attribute_name"，将其替换为

@subscription = Subscription.find_by_email(params[:email])

或者无需写下额外的代码。无需获取所有订阅。删除使用

@subscription = Subscription.find_by_email(params[:email])
or
@subscription = Subscription.find(params[:id])

if @subscription.destroy
  flash[:notice] = "You have been unsubscribed"
  redirect_to root_path
end

使用表单Rails 4删除订阅

2 个答案: