Ruby on rails 在Rails中形成对象

下面的示例代码是一个故意尝试使用表单对象的示例，在这种情况下，使用表单对象可能会有过大的杀伤力。尽管如此：它显示了我面临的问题：

我有两种型号：一个

用户

和一个

电子邮件

：

# app/models/user.rb
class User < ApplicationRecord
  has_many :emails
end

---

注意：表单对象上的验证。如果

用户表单

的

名称

属性为空，或者如果

电子邮件表单

数组中的任何

电子邮件表单

对象的

电子邮件文本

属性为空，则认为该表单无效

为简洁起见：我将仅介绍使用

用户表单的
新建
和
创建
操作：

# app/controllers/user_controller.rb
class UsersController < ApplicationController

  def new
    @user_form = UserForm.new
    @user_form.email_forms = [EmailForm.new, EmailForm.new, EmailForm.new]
  end

  def create
    @user_form = UserForm.new(user_form_params)

    if @user_form.save
      redirect_to users_path, notice: 'User was successfully created.' 
    else
      render :new
    end 
  end

  private

  def user_form_params
    params.require(:user_form).permit(:name, {email_forms: [:_destroy, :id, :email_text, :user_id]})
  end
end

应该发生的是表单应该被重新呈现，并且没有任何内容被持久化，因为form_对象无效：所有三封关联的电子邮件都不能为空。但是：form_对象认为它是有效的，它在
persist中爆炸UserForm
上的code>方法。它突出显示
Email.create（用户：用户，Email\u文本：Email.Email\u文本）
行，并显示：

[“0”，{“email\u text”=>“test\u email\u 1}]：数组的未定义方法“email\u text”

很明显，有两件事正在发生：嵌套的验证似乎不起作用，而且我在从params散列重新生成每个电子邮件时遇到困难

我已经检查过的资源：

#app/models/user.rb
class User < ApplicationRecord
  has_many :emails
end

#app/models/email.rb
class Email < ApplicationRecord
  belongs_to :user
end

#app/controllers/users_controller.rb
class UsersController < ApplicationController

  def index
    @users = User.all
  end

  def new
    @user_form = UserForm.new
    @user_form.emails = [EmailForm.new, EmailForm.new, EmailForm.new]
  end

  def create
    @user_form = UserForm.new(user_form_params)
    if @user_form.save
      redirect_to users_path, notice: 'User was successfully created.'
    else
      render :new 
    end 
  end


  private

  def user_form_params
      params.require(:user_form).permit(:name, {emails_attributes: [:email_text]})
  end
end

#app/forms/user_form.rb
class UserForm
  include ActiveModel::Model

  attr_accessor :name, :emails

  validates :name, presence: true
  validate  :all_emails_valid


  def emails_attributes=(attributes)
    @emails ||= []
    attributes.each do |_int, email_params|
      email = EmailForm.new(email_params)
      @emails.push(email)
    end
  end

  def save
    if valid?
      persist!
      true
    else
      false
    end
  end

  private

  def persist!
    user = User.new(name: name)
    new_emails = emails.map do |email_form|
      Email.new(email_text: email_form.email_text)
    end
    user.emails = new_emails
    user.save!
  end

  def all_emails_valid
    emails.each do |email_form|
      errors.add(:base, "Email Must Be Present") unless email_form.valid?
    end
    throw(:abort) if errors.any?
  end
end


app/forms/email_form.rb
class EmailForm 
  include ActiveModel::Model

  attr_accessor :email_text, :user_id
  validates :email_text, presence: true
end

app/views/users/new.html.erb
<h1>New User</h1>

<%= render 'form', user_form: @user_form %>
<%= link_to 'Back', users_path %>


#app/views/users/_form.html.erb
<%= form_for(user_form, url: users_path) do |f| %>

  <% if user_form.errors.any? %>
    <div id="error_explanation">
      <h2><%= pluralize(user_form.errors.count, "error") %> prohibited this User from being saved:</h2>

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

  <div class="field">
    <%= f.label :name %>
    <%= f.text_field :name %>
  </div>


  <%= f.fields_for :emails do |email_form| %>
    <div class="field">
      <%= email_form.label :email_text %>
      <%= email_form.text_field :email_text %>
    </div>
  <% end %>


  <div class="actions">
    <%= f.submit %>
  </div>
<% end %>


看起来很有希望，但我很难让它发挥作用
我已经尝试了使用virtus gem和reform rails gem的实现。我还为这两个实现发布了悬而未决的问题：然后
我曾尝试插入
接受嵌套的属性，但在弄清楚如何利用表单对象和嵌套表单对象（如本代码示例中）时遇到了问题。问题的一部分是
有许多
和
接受
的嵌套属性似乎没有包含在
ActiveModel:：Model
中


非常感谢您提供有关如何让此表单对象执行预期操作的任何指导！谢谢
 完整答案

型号：

#app/models/user.rb
class User < ApplicationRecord
  has_many :emails
end

#app/models/email.rb
class Email < ApplicationRecord
  belongs_to :user
end

#app/controllers/users_controller.rb
class UsersController < ApplicationController

  def index
    @users = User.all
  end

  def new
    @user_form = UserForm.new
    @user_form.emails = [EmailForm.new, EmailForm.new, EmailForm.new]
  end

  def create
    @user_form = UserForm.new(user_form_params)
    if @user_form.save
      redirect_to users_path, notice: 'User was successfully created.'
    else
      render :new 
    end 
  end


  private

  def user_form_params
      params.require(:user_form).permit(:name, {emails_attributes: [:email_text]})
  end
end

#app/forms/user_form.rb
class UserForm
  include ActiveModel::Model

  attr_accessor :name, :emails

  validates :name, presence: true
  validate  :all_emails_valid


  def emails_attributes=(attributes)
    @emails ||= []
    attributes.each do |_int, email_params|
      email = EmailForm.new(email_params)
      @emails.push(email)
    end
  end

  def save
    if valid?
      persist!
      true
    else
      false
    end
  end

  private

  def persist!
    user = User.new(name: name)
    new_emails = emails.map do |email_form|
      Email.new(email_text: email_form.email_text)
    end
    user.emails = new_emails
    user.save!
  end

  def all_emails_valid
    emails.each do |email_form|
      errors.add(:base, "Email Must Be Present") unless email_form.valid?
    end
    throw(:abort) if errors.any?
  end
end


app/forms/email_form.rb
class EmailForm 
  include ActiveModel::Model

  attr_accessor :email_text, :user_id
  validates :email_text, presence: true
end

app/views/users/new.html.erb
<h1>New User</h1>

<%= render 'form', user_form: @user_form %>
<%= link_to 'Back', users_path %>


#app/views/users/_form.html.erb
<%= form_for(user_form, url: users_path) do |f| %>

  <% if user_form.errors.any? %>
    <div id="error_explanation">
      <h2><%= pluralize(user_form.errors.count, "error") %> prohibited this User from being saved:</h2>

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

  <div class="field">
    <%= f.label :name %>
    <%= f.text_field :name %>
  </div>


  <%= f.fields_for :emails do |email_form| %>
    <div class="field">
      <%= email_form.label :email_text %>
      <%= email_form.text_field :email_text %>
    </div>
  <% end %>


  <div class="actions">
    <%= f.submit %>
  </div>
<% end %>

视图：

#app/models/user.rb
class User < ApplicationRecord
  has_many :emails
end

#app/models/email.rb
class Email < ApplicationRecord
  belongs_to :user
end

#app/controllers/users_controller.rb
class UsersController < ApplicationController

  def index
    @users = User.all
  end

  def new
    @user_form = UserForm.new
    @user_form.emails = [EmailForm.new, EmailForm.new, EmailForm.new]
  end

  def create
    @user_form = UserForm.new(user_form_params)
    if @user_form.save
      redirect_to users_path, notice: 'User was successfully created.'
    else
      render :new 
    end 
  end


  private

  def user_form_params
      params.require(:user_form).permit(:name, {emails_attributes: [:email_text]})
  end
end

#app/forms/user_form.rb
class UserForm
  include ActiveModel::Model

  attr_accessor :name, :emails

  validates :name, presence: true
  validate  :all_emails_valid


  def emails_attributes=(attributes)
    @emails ||= []
    attributes.each do |_int, email_params|
      email = EmailForm.new(email_params)
      @emails.push(email)
    end
  end

  def save
    if valid?
      persist!
      true
    else
      false
    end
  end

  private

  def persist!
    user = User.new(name: name)
    new_emails = emails.map do |email_form|
      Email.new(email_text: email_form.email_text)
    end
    user.emails = new_emails
    user.save!
  end

  def all_emails_valid
    emails.each do |email_form|
      errors.add(:base, "Email Must Be Present") unless email_form.valid?
    end
    throw(:abort) if errors.any?
  end
end


app/forms/email_form.rb
class EmailForm 
  include ActiveModel::Model

  attr_accessor :email_text, :user_id
  validates :email_text, presence: true
end

app/views/users/new.html.erb
<h1>New User</h1>

<%= render 'form', user_form: @user_form %>
<%= link_to 'Back', users_path %>


#app/views/users/_form.html.erb
<%= form_for(user_form, url: users_path) do |f| %>

  <% if user_form.errors.any? %>
    <div id="error_explanation">
      <h2><%= pluralize(user_form.errors.count, "error") %> prohibited this User from being saved:</h2>

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

  <div class="field">
    <%= f.label :name %>
    <%= f.text_field :name %>
  </div>


  <%= f.fields_for :emails do |email_form| %>
    <div class="field">
      <%= email_form.label :email_text %>
      <%= email_form.text_field :email_text %>
    </div>
  <% end %>


  <div class="actions">
    <%= f.submit %>
  </div>
<% end %>

app/views/users/new.html.erb
新用户
#app/views/users/_form.html.erb
禁止保存此用户：



您是否查看了“”的接受嵌套属性。。。这加上gem
cocoon
基本上消除了处理嵌套属性的所有困难。@SteveTurczyn是的，我已经看过了
为
接受嵌套属性。我在弄清楚如何在表单对象中为
实现
accepts\u nested\u attributes\u时遇到了很多麻烦。我更新了我的问题，表达了对这条路线的尝试。说真的，看看“茧”。这让一切变得容易。如果您在实现“cocoon”时遇到问题，请使用标签
RubyonRails
和
cocoon gem
发布问题，gem就在这里。。。我有同样的问题，用户模型有一个关联的模型地址。如果地址记录是否为空，如何设计formobject。如果地址记录为空，则应呈现地址字段，否则不应显示。