Question

我是 collection_select 的新手。我观看了几个Youtube视频，并在RailsGuides上阅读了有关collection_select的信息，并在Stack Overflow上进行了搜索。但是我很难理解哪些数据在哪里以及collection_select有效。

这导致我写错了我自己的collection_select。什么信息在哪里，以及我自己的collection_select中应该包含哪些信息？

我目前正在构建一个轻量级CRM并尝试为交易分配:contact_id，但当我尝试这样做时，我不断收到错误，我在下面提供了截图。错误说明：

1错误禁止此用户被保存：


联系必须存在

Screenshot of error

这是我的 deals_controller.rb 文件：

class DealsController < ApplicationController

def index
@deals = Deal.all
end

def new
@deal = Deal.new
end

def show
@deal = Deal.find(params[:id])
end

def create
@deal = Deal.new(deal_params)
if @deal.save
redirect_to organization_contact_deal_url(@deal)
else
render :new
end
end

private
def deal_params
params.require(:deal).permit(:deal_name, :deal_amount, :contact_id)
end

end

以下是我的 new.html.erb 交易文件：

 <%= form_with scope: :deal, url: organization_contact_deals_path, local: true do |form| %>
 <% if @deal.errors.any? %>
 <div id="error_explanation">
 <h2><%= pluralize(@deal.errors.count, "error") %> prohibited this user from being saved: </h2>

  <ul>
  <% @deal.errors.full_messages.each do |message| %>
  <li><%= message %></li>
  <% end %>
  </ul>
  </div>
  <% end %>

  <p>
  <%= form.label :deal_name %>
  <%= form.text_field :deal_name %>
  </p>

  <p>
  <%= form.label :contact_id %>

  <%= form.collection_select(:contact_id, Contact.all, :id, :full_name) %>

 </p>

 <p>
 <%= form.submit %>
 </p>

 <% end %>

这是我的 schema.rb ：

ActiveRecord::Schema.define(version: 20171209203509) do

create_table "contacts", force: :cascade do |t|
t.string "contact_first_name"
t.string "contact_last_name"
t.integer "organization_id"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.index ["organization_id"], name: 
"index_contacts_on_organization_id"
end

create_table "deals", force: :cascade do |t|
t.string "deal_name"
t.string "deal_amount"
t.integer "contact_id"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.index ["contact_id"], name: "index_deals_on_contact_id"
end

create_table "organizations", force: :cascade do |t|
t.string "organization_name"
t.string "organization_industry"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end

end

这是我的 deal.rb 模型文件：

class Deal < ApplicationRecord
belongs_to :contact
end

这是我的 contact.rb 模型文件：

class Contact < ApplicationRecord
belongs_to :organization
has_many :deals, dependent: :destroy

def full_name
"#{contact_first_name} #{contact_last_name}"
end
end

以下是路线：

                        Prefix Verb   URI Pattern                                                                   Controller#Action
         welcome_index GET    /welcome/index(.:format)                                                      
         welcome#index
         organization_contact_deals GET    /organizations/:organization_id/contacts/:contact_id/deals(.:format)          deals#index
                       POST   /organizations/:organization_id/contacts/:contact_id/deals(.:format)          deals#create
         new_organization_contact_deal GET /organizations/:organization_id/contacts/:contact_id/deals/new(.:format)      deals#new
         edit_organization_contact_deal GET    /organizations/:organization_id/contacts/:contact_id/deals/:id/edit(.:format) deals#edit
         organization_contact_deal GET    /organizations/:organization_id/contacts/:contact_id/deals/:id(.:format)      deals#show
                       PATCH  /organizations/:organization_id/contacts/:contact_id/deals/:id(.:format)      deals#update
                       PUT    /organizations/:organization_id/contacts/:contact_id/deals/:id(.:format)      deals#update
                       DELETE /organizations/:organization_id/contacts/:contact_id/deals/:id(.:format)      deals#destroy
        organization_contacts GET    /organizations/:organization_id/contacts(.:format)                            contacts#index
                       POST   /organizations/:organization_id/contacts(.:format)                            contacts#create
        new_organization_contact GET    /organizations/:organization_id/contacts/new(.:format)                        contacts#new
        edit_organization_contact GET    /organizations/:organization_id/contacts/:id/edit(.:format)                   contacts#edit
        organization_contact GET    /organizations/:organization_id/contacts/:id(.:format)                        contacts#show
                       PATCH  /organizations/:organization_id/contacts/:id(.:format)                        contacts#update
                       PUT    /organizations/:organization_id/contacts/:id(.:format)                        contacts#update
                       DELETE /organizations/:organization_id/contacts/:id(.:format)                        contacts#destroy
         organizations GET    /organizations(.:format)                                                      organizations#index
                       POST   /organizations(.:format)                                                      organizations#create
        new_organization GET    /organizations/new(.:format)                                                  organizations#new
        edit_organization GET    /organizations/:id/edit(.:format)                                             organizations#edit
         organization GET    /organizations/:id(.:format)                                                  organizations#show
                       PATCH  /organizations/:id(.:format)                                                  organizations#update
                       PUT    /organizations/:id(.:format)                                                  organizations#update
                       DELETE /organizations/:id(.:format)                                                  organizations#destroy
                  root GET    /

这是我的 routes.rb 文件：

Rails.application.routes.draw do
get 'welcome/index'

resources :organizations do
resources :contacts do
resources :deals
end
end

root 'welcome#index'
end

修改：

我更新了我的contact.rb文件，new.html.erb表单和deals_controller.rb。一旦这个问题得到解决，我将留下更详细的编辑日志。

更改后的新错误：

ActionController::UrlGenerationError in DealsController#create

No route matches {:action=>"show", :contact_id=>"2", 
:controller=>"deals", :organization_id=>#<Deal id: 6, deal_name: 
"Office365 deal", deal_amount: nil, contact_id: 2, created_at: "2017-
12-10 03:35:48", updated_at: "2017-12-10 03:35:48">}, missing 
required keys: [:id]

@deal = Deal.new(deal_params)
if @deal.save
**redirect_to organization_contact_deal_url(@deal)**
else
render :new
end

Answer 1

您从允许的参数中遗漏了:contact_id：

def deal_params
  params.require(:deal).permit(:deal_name, :deal_amount, :contact_id)
end

在联系模型中添加full_name实例方法

class Contact < ApplicationRecord
  belongs_to :organization
  has_many :deals, dependent: :destroy

  def full_name
    "#{first_name} #{last_name}"
  end
end

以您的形式：

<%= form.collection_select :contact_id, Contact.all, :id, :full_name %>

在您的控制器中创建操作：

 def create
   @deal = Deal.new(deal_params)
   if @deal.save
     redirect_to @deal
   else
     render :new
   end
 end

如何调试为什么collection_select不起作用？

1 个答案: