Question

我正在尝试使用paperclip并更新列表，但每当我在表单上执行此操作时，都会收到此错误。

ListingsController＃update中的ArgumentError 错误的参数数量（2对1）

代码如下，如果@ listing.update（listing_params）

，那么突出显示为错误的行将以开头
@listing = Listing.new respond_to do |format| if @listing.update(listing_params) format.html { redirect_to @listing, notice: 'Listing was successfully updated.' } format.json { head :no_content } else

这是应用程序跟踪

app/controllers/listings_controller.rb:45:in `block in update' app/controllers/listings_controller.rb:44:in `update'

有什么我缺少的，语法方面的，还是其他的东西？非常感谢。

编辑：

我的列表模型（listings.rb）的代码如下

class Listing < ActiveRecord::Base has_attached_file :image, :styles => { :medium => "200x", :thumb => "100x100>" }, :default_url => "default.jpg" end

我的表单（_form.html.erb）如下：

<%= form_for @listing, :html => { :multipart => true } do |f| %> <% if @listing.errors.any? %> <div id="error_explanation"> <h2><%= pluralize(@listing.errors.count, "error") %> prohibited this listing from being saved:</h2> <ul> <% @listing.errors.full_messages.each do |msg| %> <li><%= msg %></li> <% end %> </ul> </div> <% end %> <div class="field"> <%= f.label :name %><br> <%= f.text_field :name, class: "form-control" %> </div> <div class="field"> <%= f.label :description %><br> <%= f.text_area :description, class: "form-control" %> </div> <div class="field"> <%= f.label :price %><br> <%= f.text_field :price, class: "form-control" %> </div> <div class="form-group"> <%= f.file_field :image, class: "form-control" %> </div> <div class="actions"> <%= f.submit class: "btn btn-primary" %> </div> <% end %>

Answer 1

您正在更新商家信息。你需要删除

@listing = Listing.new

通过写这个，你正在初始化一个列表。这是一种更新方法，因此您需要找到您的商家信息而不是初始化新商品，请尝试

@listing = Listing.find(params[:id]) #this will find your listing with id
respond_to do |format|
  if @listing.update(listing_params) #this will update the listing which you find above
    format.html { redirect_to @listing, notice: 'Listing was successfully updated.' }
    format.json { head :no_content }
  else
    #code
  end
end

Answer 2

您更新控制器方法应如下所示;

def update
    @listing = Listing.find(params[:id]) #find item you want to update

    respond_to do |format|
      if @listing.update(listing_params) # the refer to it and update it
        format.html { redirect_to @listing, notice: 'Listing was successfully updated.' }
        format.json { head :no_content }
      else
    end
  end

参数错误/错误的参数数量 - 我不知道这里发生了什么，

2 个答案: