更新後，文件字段在導軌4中使用載波寶石複製

Question

我正在使用導軌4和載波波形上傳文件。我有一個產品和資產模型。 Product has_many資產和嵌套表單用於保存產品中的資產。當我更新任何產品時，其資產字段會被重複，當我再次編輯同一產品時，我可以在表單中看到8個字段代替4個字段。

Product.rb

class Product < ActiveRecord::Base 

has_many :assets , :dependent => :delete_all 
accepts_nested_attributes_for :assets 

Asset.rb

class Asset < ActiveRecord::Base 
    mount_uploader :asset1, AssetUploader 
    mount_uploader :asset2, AssetUploader 
    mount_uploader :asset3, AssetUploader 
    mount_uploader :asset4, AssetUploader 
end 

產品控制器

def new 
    @product = Product.new 
    @product.assets.build 
end 

def create 
    @product = Product.new(product_params) 
    respond_to do |format| 
    if @product.save 
     format.html { redirect_to product_product_detail_path(@product), notice: 'Product was successfully created.' } 
     format.json { render action: 'show', status: :created, location: @product } 
    else 
     format.html { render action: 'new' } 
     format.json { render json: @product.errors, status: :unprocessable_entity } 
    end 
    end 
end 


def update 
    respond_to do |format| 
    if @product.update(product_params) 
     format.html { redirect_to sub_category_path(@product.sub_category_id), notice: 'Product was successfully updated.' } 
     format.json { head :no_content } 
    else 
     format.html { render action: 'edit' } 
     format.json { render json: @product.errors, status: :unprocessable_entity } 
    end 
    end 
end 

new_html.erb產品

<%= form_for(@product, html: { multipart: true }) do |f| %> 
    <%= f.fields_for :assets do |asset| %> 
    <div class="field"> 
    <%= asset.label :asset, "File #1" %> 
    <% unless asset.object.asset1.file.nil? %> 
     <%= image_tag(asset.object.asset1.url) %> 
     <p><% asset.object.asset1.file.filename %></p> 
     <p style="float:left">Change File?</p> 
    <% end %> 
    <%= asset.file_field :asset1 %> 
</div> 

<div class="field"> 
    <%= asset.label :asset, "File #2" %> 
    <% unless asset.object.asset2.file.nil? %> 
     <%= image_tag(asset.object.asset2.url) %> 
     <p><% asset.object.asset2.file.filename %></p> 
     <p style="float:left">Change File?</p> 
    <% end %> 
    <%= asset.file_field :asset2 %> 
    </div> 

    <div class="field"> 
    <%= asset.label :asset, "File #3" %> 
    <% unless asset.object.asset3.file.nil? %> 
     <%= image_tag(asset.object.asset3.url) %> 
     <p><% asset.object.asset3.file.filename %></p> 
     <p style="float:left">Change File?</p> 
    <% end %> 
    <%= asset.file_field :asset3 %> 
    </div> 

    <div class="field"> 
    <%= asset.label :asset, "File #4" %> 
    <% unless asset.object.asset4.file.nil? %> 
     <%= image_tag(asset.object.asset4.url) %> 
     <p><% asset.object.asset4.file.filename %></p> 
     <p style="float:left">Change File?</p> 
    <% end %> 
    <%= asset.file_field :asset4 %> 
    </div> 
<% end %> 


<div class="actions"> 
    <%= f.submit :class=> "action-btn" %> 
</div> 
<% end %> 

最新情況：

def product_params 
    params.require(:product).permit(assets_attributes: [:asset, :asset1, :asset2, :asset3, :asset4 ]) 
end 

def edit 
end 

請幫我解決這個問題。

Answer 1

嘗試（ID爲更新）：

def product_params 
    params.require(:product).permit(assets_attributes: [:id, :asset, :asset1, :asset2, :asset3, :asset4 ]) 
end