Rails 4-在沒有數據庫的情況下驗證模型

Question

我已經按照本教程進行了學習，並為Rails 4盡了最大努力。

http://railscasts.com/episodes/219-active-model?language=en&view=asciicast

---

class Contact
  include ActiveModel::Validations
  include ActiveModel::Conversion
  extend ActiveModel::Naming

  validates :name, :email, :phone, :comment, :presence => true

  def initialize(attributes = {})
    attributes.each do |name, value|
      send("#{name}=", value)
    end
  end

  def persisted?
    false
  end

  private
  # Using a private method to encapsulate the permissible parameters is just a good pattern
  # since you'll be able to reuse the same permit list between create and update. Also, you
  # can specialize this method with per-user checking of permissible attributes.
  def contact_params
    params.require(:contact).permit(:name, :email, :phone, :comment)
  end
end

在我的控制器中：

class ContactController < ApplicationController
  def index
    @contact = Contact.new
  end

  def create
    @contact = Contact.new(params[:contact])
    if @contact.valid?
      # Todo send message here.
      render action: 'new'
    end
  end
end

在我看來：

<%= form_for @contact do |f| %>
    <%= f.label :name %>:
    <%= f.text_field :name %><br />

    <%= f.label :email %>:
    <%= f.text_field :email %><br />

    <%= f.submit %>
<% end %>

---

我收到以下異常消息：

undefined method `name' for #<Contact:0x007fd6b3bf87e0>

Answer 1

您必須將它們聲明為屬性。

attr_accessor：名稱，電子郵件，：電話，：評論

Answer 2

您可以使用ActiveAttr gem： https ： //github.com/cgriego/active_attr

Rails Cast教程： http ： //railscasts.com/episodes/326-activeattr

例：

class Contact
  include ActiveAttr::Model

  attribute :name
  attribute :email
  attribute :phone
  attribute :comment

  validates :name, :email, :phone, :comment, :presence => true
end

PS：我知道，這是一個老問題，但這可以幫助某人。

Answer 3

在Rails 4及更高版本中，它實際上更簡單：像下面這樣使用ActiveModel :: Model ：

class Contact
  include ActiveModel::Model
  attr_accessor :name, :email, :phone, :comment

  validates :name, :email, :phone, :comment, :presence => true
end