Question

items_controller.rb

class ItemsController < ApplicationController

  def index
    @items = Item.all
    render text: @items.map{ |i| "#{i.name}: #{i.price}" }.join('<br/>')
  end

  def create
    item_params = params.require(:item).permit(:name, :description, :price, :real, :weight)
    @item = Item.create(item_params)
    render text: "#{@item.id}: #{@item.name}(#{!@item.new_record?})"
  end

end

错误：缺少参数或值为空：item

Rails.root：E：/ work / my_store_2

应用程序跟踪|框架跟踪|完整追踪   app / controllers / items_controller.rb：9：在'create＆＃39;请求

参数：

{＆＃34; name＆＃34; =＆gt;＆＃34; car1＆＃34;，＆＃34;说明＆＃34; =＆gt;＆＃34;好车＆＃34;，＆＃34;价格＆＃34; = GT;＆＃34; 500000＆＃34 ;,   ＆＃34;体重＆＃34; =＆gt;＆＃34; 0＆＃34;，＆＃34;真实＆＃34; =＆gt;＆＃34; 1＆＃34;}

控制台

Started GET "/items/create?name=car1&description=good+car&price=500000&weight=0&real=1" for 127.0.0.1 at 2015-06-18 21:25:39 +0300
Processing by ItemsController#create as HTML
  Parameters: {"name"=>"car1", "description"=>"good car", "price"=>"500000", "weight"=>"0", "real"=>"1"}
Completed 400 Bad Request in 2ms

ActionController::ParameterMissing (param is missing or the value is empty: item):
  app/controllers/items_controller.rb:9:in `create'

我的错误在哪里？

Answer 1

执行params.require(:item)时，需要item参数存在。因此，create操作期望像这样的参数：{ "item" => {"name"=>"car1", "description"=>"good car", "price"=>"500000", "weight"=>"0", "real"=>"1"} }

您缺少item根密钥。

Answer 2

您错过了＆＃39;项目＆＃39;在你的表格上。添加id =＆＃34; item＆＃34;。

的字段

param丢失或值为空：item

2 个答案: