那些遇到过的问题

尝试使用accepts_nested_attributes_for和has_and_belongs_to_many,但未填充连接表

dav*_*tes 11 ruby ruby-on-rails has-and-belongs-to-many

我正在学习RoR并尝试使用accepts_nested_attributes_for和has_and_belongs_to_many来提交传统上是两种形式的信息.我在一些网站上看到它们兼容,有些网站不兼容,有些网站不知道.作为参考,我使用的是Rails 2.3.4.我尝试使用嵌套模型上的Ryan's Scraps教程对我的解决方案进行建模

从我试图调试,似乎我有两个问题,但我不知道为什么.

  1. 当我提交带有嵌套模型的表单时,只会发布部分嵌套模型信息.我只获得第一个字段,而不是用户可能选择的"n"个字段
  2. 在发布的单个字段中,没有为我为HABTM关系创建的连接表中插入任何行.

这是我的插入尝试的一段代码和相应的日志:

律师模型: 

class Attorney < ActiveRecord::Base 
  has_and_belongs_to_many :associations
  accepts_nested_attributes_for :associations, :reject_if => proc { |a| a['name'].blank? }
end
Run Code Online (Sandbox Code Playgroud)

协会模型:

class Association < ActiveRecord::Base
  has_and_belongs_to_many :attorneys
  accepts_nested_attributes_for :attorneys
  validates_presence_of :name, :message => "Please enter an association name."
end
Run Code Online (Sandbox Code Playgroud)

律师控制员:

def new
  @attorney = Attorney.new
  @attorney.associations.build

  respond_to do |format|
    format.html # new.html.erb
    format.xml  { render :xml => @attorney }
  end
end

def create
  @attorney = Attorney.new(params[:attorney])

  respond_to do |format|
    if @attorney.save
      flash[:notice] = 'Attorney was successfully created.'
      format.html { redirect_to(@attorney) }
      format.xml  { render :xml => @attorney, :status => :created, :location => @attorney }
    else
      format.html { render :action => "new" }
      format.xml  { render :xml => @attorney.errors, :status => :unprocessable_entity }
    end
  end
end
Run Code Online (Sandbox Code Playgroud)

律师的新观点:

<% form_for(@attorney, :html => {:multipart => true}) do |f| %>
  <%= f.error_messages %>
 <%= f.label :"First name" %> 
 <%= f.text_field :firstname %><br>

 <%= f.label :"Last Name" %> 
 <%= f.text_field :lastname %><br>

 <%= f.label :"Attorney Type" %> 
 <%= f.collection_select :member_type_id, MemberType.all, :id, :name %><br>

 <%= f.text_area :bio, :cols => 70, :rows => 20 %><br><br>

 <%= f.label :"Attorney Location" %> 
 <%= f.collection_select :office_location_id, OfficeLocation.all, :id, :location %><br>

 <div id="associations">
      <%= render :partial => 'shared/membership' %>
 </div>
 <%= add_association_link "Add Association" %>
    <%= f.submit 'Create' %>
<% end %>
Run Code Online (Sandbox Code Playgroud)

会员资格部分:

<div class="association">
  <% fields_for :associations do |assoc_form| %>
    <%= assoc_form.collection_select(:association_id, Association.find(:all), :id, :name, :include_blank => true) %>
Run Code Online (Sandbox Code Playgroud)

<%= link_to_function"remove","$(this).up('.association').remove()"%> <%= link_to'New Association',new_association_path%> <%end%>

律师帮助链接:

def add_association_link(name)
  link_to_function name do |page|
    page.insert_html :bottom, :associations, :partial => 'shared/membership', :object => AssociationsAttorneys.new
  end
end
Run Code Online (Sandbox Code Playgroud)

加入表迁移:

class CreateAssociationsAttorneys < ActiveRecord::Migration
  def self.up
    create_table :associations_attorneys do |t|
      t.references :attorney, :null => false
      t.references :association, :null => false
      t.timestamps
    end
  end

  def self.down
    drop_table :associations_attorneys
  end
end
Run Code Online (Sandbox Code Playgroud)

日志捕获:

    Processing AttorneysController#new (for 127.0.0.1 at 2009-12-04 08:16:19) [GET]
Rendering template within layouts/default
Rendering attorneys/new
  [4;35;1mMemberType Load (0.4ms)[0m   [0mSELECT * FROM "member_types" [0m
  [4;36;1mOfficeLocation Load (18.6ms)[0m   [0;1mSELECT * FROM "office_locations" [0m
  [4;35;1mAssociation Load (0.6ms)[0m   [0mSELECT * FROM "associations" [0m
Rendered shared/_membership (3.5ms)
  [4;36;1mCACHE (0.0ms)[0m   [0;1mSELECT * FROM "associations" [0m
Rendered shared/_membership (1.5ms)
Rendered shared/_nav (0.6ms)
Rendered shared/_footer (0.1ms)
Completed in 149ms (View: 114, DB: 20) | 200 OK [http://localhost/attorneys/new]

Processing ApplicationController#index (for 127.0.0.1 at 2009-12-04 08:16:19) [GET]

Processing AttorneysController#create (for 127.0.0.1 at 2009-12-04 08:16:57) [POST]
  Parameters: {"commit"=>"Create", "authenticity_token"=>"Jh7aMCcOY7jUu/D1YtiCswg2n6iwqnS98VnVn46psp0=", "associations"=>{"association_id"=>"3"}, "attorney"=>{"birthstate"=>"Alabama", "office_location_id"=>"1", "birthdate"=>"December 3, 2009", "birthcity"=>"Test", "middlename"=>"Test", "lastname"=>"Testing", "image_temp"=>"", "member_type_id"=>"2", "firstname"=>"Test", "bio"=>"testing testing testing", "suffix"=>"", "email"=>"testing@test.com"}}
  [4;35;1mAttorney Load (15.6ms)[0m   [0mSELECT "attorneys".id FROM "attorneys" WHERE ("attorneys"."email" = 'testing@test.com') LIMIT 1[0m
  [4;36;1mAttorney Create (0.8ms)[0m   [0;1mINSERT INTO "attorneys" ("birthstate", "created_at", "birthdate", "office_location_id", "birthcity", "updated_at", "middlename", "lastname", "firstname", "member_type_id", "suffix", "bio", "image", "email") VALUES('Alabama', '2009-12-04 15:16:57', 'December 3, 2009', 1, 'Test', '2009-12-04 15:16:57', 'Test', 'Testing', 'Test', 2, '', 'testing testing testing', NULL, 'testing@test.com')[0m
Redirected to http://localhost:3000/attorneys/11
Completed in 150ms (DB: 16) | 302 Found [http://localhost/attorneys]
Run Code Online (Sandbox Code Playgroud)

我可以看到关联"=> {"association_id"=>"3"}它只获得了我对特定人员的多个关联中的最后一个,并且它没有在连接表中创建任何条目.我的代码出了问题？

EmF*_*mFi 27

你们两个在这里有问题,不幸的是其中一个被另一个掩盖了.

这两个问题源于这一部分观点:

<div class="association">
  <% fields_for :associations do |assoc_form| %>
    <%= assoc_form.collection_select(:association_id, Association.find(:all),
      :id, :name, :include_blank => true) %>
Run Code Online (Sandbox Code Playgroud)

问题1:你误解了accept_nested_fields_for的作用.

accepts_nested_fields_for用于创建和修改表单中的相关对象.它可以用来填充连接表,这是你想要做的事情.但是,使用accepts_nested_fields_for填充连接表是不可能的HABTM关系.如果你想创建一个与新律师联系的新协会,那么很好地使用accepts_nested_fields_for.或者,如果您有一个丰富的连接模型,需要每个记录的附加信息.

问题2:您没有将此表单中的字段链接到律师表格.使用accepts_nested_fields_for是必要的.

我们已经确定accepted_nested_fields_for不是你需要完成的,但是,你仍然没有将select association_id字段与表单相关联.这就是为什么params [associations] [association_id]被设置而不是params [attorney] [association] [association_id].

问题3:表单结构完全错误,因为它看起来像你想要完成的.

有太多需要纠正我给予适当的分解.您最好查看复杂表单示例存储库.这是accepts_nested_attributes_for的一个工作示例,它不处理任何HABTM关系,但它应该教你需要知道的每件事.以下更正的代码是您需要的90%.上面链接的复杂表单示例将教您填写add_association_link和create_association_link空白时需要了解的内容.

更正涉及以下步骤:

  1. 创建连接模型,并将关系更改为a到多个,接受连接模型上的嵌套属性.
  2. 在建筑物方面对控制器进行微调.
  3. 将表单构建器对象传递给partial.
  4. 重写部分中的表单,以便重点关注新创建的连接模型.

您可以通过以下更改来完成此操作.

class Attorney < ActiveRecord::Base
  has_many :attorney_associations
  has_many :associations, :through => :attorney_associations

  accepts_nested_attributes_for :attorney_associations, :reject_if => proc { |a| 
     a['association_id'].blank? }
  accepts_nested_attributes_for :associations, :reject_if => proc {|a|
     a['name'].blank?}
end

class AttorneyAssociations < ActiveRecord::Base
  belongs_to :attorney
  belongs_to :association
end
Run Code Online (Sandbox Code Playgroud)

律师控制员:

def new
  @attorney = Attorney.new
  @attorney.associations.build
  @attorney.attorney_associations.build


  respond_to do |format|
    format.html # new.html.erb
    format.xml  { render :xml => @attorney }
  end
end
Run Code Online (Sandbox Code Playgroud)

新律师查看:

<% form_for(@attorney, :html => {:multipart => true}) do |f| %>
  <%= f.error_messages %>
 <%= f.label :"First name" %> 
 <%= f.text_field :firstname %><br>

 <%= f.label :"Last Name" %> 
 <%= f.text_field :lastname %><br>

 <%= f.label :"Attorney Type" %> 
 <%= f.collection_select :member_type_id, MemberType.all, :id, :name %><br>

 <%= f.text_area :bio, :cols => 70, :rows => 20 %><br><br>

 <%= f.label :"Attorney Location" %> 
 <%= f.collection_select :office_location_id, OfficeLocation.all, :id, :location %><br>

 <div id="associations">
   <% f.fields_for :attorney_association do |aa_form| %>
     <%= render :partial => 'attorney_association', :locals => {:f => aa_form} %>
   <% end %>
   <%= add_association_link "Add Another Existing Association" %>
   <% f.fields_for :associations do |assoc_form| %>
     <%= render :partial => 'attorney', :locals => {:f => assoc_form} %>       
   <%= create_association_link, "Create a New Association for this Attorney" %>
 </div>



 <%= f.submit 'Create' %>
<% end %>
Run Code Online (Sandbox Code Playgroud)

我假设add_association_link是一个javascript助手,它创建一个链接来克隆Membership部分的空实例.create_association_link是类似帮助器的占位符,它将为新关联添加部分.

律师协会部分:

  <div class="attorney_association">
    <%= f.collection_select(:association_id, Association.find(:all),
      :id, :name, :include_blank => true) %>
    <%= link_to_function "remove", "$(this).up('.attorney_association').remove()" %>
  </div>
Run Code Online (Sandbox Code Playgroud)

协会部分:

  <div class="association">
    <%= f.label_for :name %>
    <%= f.text_field :name %>
    <%= link_to_function "remove", "$(this).up('.attorney_association').remove()" %>
  </div>
Run Code Online (Sandbox Code Playgroud)

归档时间：

查看次数：

11300 次

最近记录：

15 年，10 月 前
相关归档
在Rails中 - 有一个rails方法将换行符转换为<br>吗？ 111
如何知道今天的日期是否在日期范围内？ 78
使用Devise时如何在注册后重定向用户？ 22
循环遍历数组 22
如何在rails中将数组保存到数据库 22
如何在不重复缩进代码的情况下在HAML中执行if/else 16
在Ruby中队列而不是方法链和规则而不是条件 16
Rails:漂亮的打印JSON没有过度杀伤力 14
将其他参数传递给Rails生成模型？ 11
如何在 Ruby 中关闭和删除文件？ 9
难疑归档
深度克隆对象 2135
在JavaScript中定义枚举的首选语法是什么？ 1982
你如何断言在JUnit 4测试中抛出某个异常？ 1915
如何从git repo中删除文件？ 1795
计算C#中的相对时间 1461
在Visual Studio中使用Git 1452
在Chrome中停用相同的来源政策 1443
谁正在侦听Mac OS X上的给定TCP端口？ 1267
在Python中使用大写字母和数字生成随机字符串 1247
如何在Java中创建通用数组？ 1045