RoR錯誤的參數數量（0表示1）形式

Question

嗨，我正在嘗試創建一個表單，同時創建一個列表並將產品與之關聯。

問題在於表格不斷提高

參數數量錯誤（0代表1）

提取的來源（第10行附近）：

     7:     <%= f.text_area :description, placeholder:
     8:     "Compose a description for it ..." %>
     9: </div>
     10: <%= l.fields_for :products do |builder| %>
     11: <%= render 'shared/product_form', :l => builder %>
     12: <% end %>
     13: <%= l.submit "Create", class: "btn btn-large btn-primary" %>

應用程序跟蹤為

    app/views/shared/_list_form.html.erb:10:in `block in        _app_views_shared__list_form_html_erb__184644094_33330696'
    app/views/shared/_list_form.html.erb:1:in `_app_views_shared__list_form_html_erb__184644094_33330696'
    app/views/lists/new.html.erb:7:in `_app_views_lists_new_html_erb__973495114_33282228'

代碼如下：

- -視圖 - -

--list_form--

    <%= form_for(@list) do |f| %>
        <%= render 'shared/error_messages', object: f.object %>
        <div class="field">
    <%= f.text_field :name, placeholder:
              "Come up with a name for your list" %>

    <%= f.text_area :description, placeholder:
              "Compose a description for it ..." %>
        </div>
        <%= f.fields_for :products do |builder| %>
        <%= render 'shared/product_form', :f => builder %>
        <% end %>
        <%= f.submit "Create", class: "btn btn-large btn-primary" %>
        <% end %>

--product_form--

     <%= f.text_field :name, "Name:" %>
     <%= f.text_area :description, :rows => 3 %>

- -模型 - -

-列表-

      class List < ActiveRecord::Base
         attr_accessible :description, :name
         belongs_to :user
         has_many :products, :dependent => :destroy
         accepts_nested_attributes_for :products,  :reject_if => lambda { |a|                                 a[:name].blank? }, :allow_destroy => true

         has_many :list_categorization
         has_many :category, :through => :list_categorization

         validates :user_id, presence: true
         validates :name, presence: true, length: {maximum: 10}
         validates :description, length: {maximum: 140}

         default_scope order: 'lists.created_at DESC'

         def categorize!(category_id)
             list_categorization.create!(category_id: category_id)
         end
      end

- 產品 -

    class Product < ActiveRecord::Base
         attr_accessible :description, :donated, :name
         validates :list_id, presence: true
         belongs_to :list
    end

---控制器--- --list_controller--

   def new
       @list = List.new
       @products = @list.products.build
   end

   def create
       @list = current_user.lists.build(params[:list]) if signed_in?
       if @list.save
       flash[:success] ="List " + @list.name + "created!" 
       render 'new'
   end

--product_controller--

  def new
      @product = Product.new
  end

  def create
      @product = @product.build(params[:product]) if signed_in?
      if @product.save
      flash[:success] ="Product " + @product.name + "created!" 
  end

您是對的，我實際上是在發布此信息后才意識到的，但是現在在嘗試提交表單時會發生這種情況：

該表格包含1個錯誤。 *名稱不能為空

如果很難，我會​​正確地填充它，這就是通過的原因

---！ruby / hash：ActiveSupport :: HashWithIndifferentAccess utf8：✓authenticity_token：38CXjVORlj2RBgoTetIMoHomcVgOIlBU5rW3NTgkRkU = list：！ruby / hash：ActiveSupport :: HashWithIndifferentAccess名稱：列表描述/由： '0'：！ruby / hash：ActiveSupport :: HashWithIndifferentAccess名稱：p1說明：這是產品提交：創建操作：創建控制器：列表

Answer 1

l從哪里來的？ 我很確定您需要將其更改為f ：

<%= form_for(@list) do |f| %>
  <%= render 'shared/error_messages', object: f.object %>
  <div class="field">
    <%= f.text_field :name, placeholder: "Come up with a name for your list" %>
    <%= f.text_area :description, placeholder: "Compose a description for it ..." %>
  </div>
  <%= f.fields_for :products do |builder| %>
    <%= render 'shared/product_form', :l => builder %>
  <% end %>
  <%= f.submit "Create", class: "btn btn-large btn-primary" %>
<% end %>

更新資料

您的代碼有一些問題。 首先，如果您@list = current_user.lists.build(params[:list]) if signed_in? 這意味着，如果沒有用戶登錄，則完全不會創建該對象。 進行此類操作的正確方法是在控制器中使用before_filter 。

其次@product = @product.build(params[:product])將不起作用。 您尚未初始化Product對象，並且尚未將其分配給@product 。 build也用於關聯。 您需要將其更改為@product = Product.new(params[:product]) 。

列出控制器：

before_filter :user_signed_in? # add to products controller as well
# if you need this filter only on certain actions then do:
# before_filter :user_signed_in?, only: [:new, :create]

def new
  @list = current_user.lists.build
  @products = @list.products.build
end

def create
  @list = current_user.lists.build(params[:list])
  if @list.save
    flash[:success] = "List " + @list.name + " created!"
    redirect_to lists_path # this part was missing!
  else # this was also missing
    render 'new'
  end # you had an 'if' with no 'end'
end

private

# add the following to Products controller as well, or if you
# use it a lot then place it in your application controller
def user_signed_in?
  unless signed_in?
    flash[:notice] = "You must first sign in"
    redirect_to sign_in_path
  end
end

產品控制器：

def new
  @product = Product.new
end

def create
  @product = Product.new(params[:product]
  if @product.save
    flash[:success] = "Product " + @product.name + " created!"
    redirect_to @product
  else
    render 'new'
  end
end

據我記得，通過嵌套表單保存產品時不會使用products#create操作，lists＃create操作將同時用於這兩種方法。

要了解有關嵌套表單的更多信息，請查看這些railscasts 。

更新代碼並瀏覽完這些視頻后，如果您仍然遇到錯誤，我建議創建一個新問題，因為這個問題已經變得冗長而混亂了:)

Answer 2

您忘記這樣做：

rails generate migration add_remember_token_to_users