ruby-on-rails - validates - ruby rails介绍




未初始化的常量ApplicationRecord (2)

看来您使用的是Rails 5教程,但是使用Rails 4.在Rails 5中,所有模型都从ApplicationRecord继承,而来自ActiveRecord::Base Rails 4

立即修复:

class User < ActiveRecord::Base
...
end

长期修复,切换到Rails 5并学习Rails 5

我在网上的铁轨教程书上工作,当我去http:// localhost:3000 /我得到以下错误消息

“未初始化的常量ApplicationRecord”

它给了我下面的代码,突出显示第一行。

class User < ApplicationRecord
  attr_accessor :remember_token
  before_save { self.email = email.downcase }
  validates :name,  presence: true, length: { maximum: 50 }
  VALID_EMAIL_REGEX = /\A[\w+\-.][email protected][a-z\d\-.]+\.[a-z]+\z/i
  validates :email, presence: true, length: { maximum: 255 },

这是我的application.html.erb文件:

<!DOCTYPE html>
<html>
  <head>
    <title><%= full_title(yield(:title)) %></title>
    <%= stylesheet_link_tag "application", media: "all",
                                           "data-turbolinks-track" => true %>
    <%= javascript_include_tag "application", "data-turbolinks-track" => true %>
    <%= csrf_meta_tags %>
    <%= render 'layouts/shim' %>
  </head>
  <body>
    <%= render 'layouts/header' %>
    <div class="container">
      <% flash.each do |message_type, message| %>
        <div class="alert alert-<%= message_type %>"><%= message %></div>
      <% end %>
      <%= yield %>
      <%= render 'layouts/footer' %>
      <%= debug(params) if Rails.env.development? %>
    </div>
  </body>
</html>

和我的user.rb文件:

class User < ApplicationRecord
  attr_accessor :remember_token
  before_save { self.email = email.downcase }
  validates :name,  presence: true, length: { maximum: 50 }
  VALID_EMAIL_REGEX = /\A[\w+\-.][email protected][a-z\d\-.]+\.[a-z]+\z/i
  validates :email, presence: true, length: { maximum: 255 },
                    format: { with: VALID_EMAIL_REGEX },
                    uniqueness: { case_sensitive: false }
  has_secure_password
  validates :password, presence: true, length: { minimum: 6 }

  # Returns the hash digest of the given string.
  def User.digest(string)
    cost = ActiveModel::SecurePassword.min_cost ? BCrypt::Engine::MIN_COST :
                                                  BCrypt::Engine.cost
    BCrypt::Password.create(string, cost: cost)
  end

  # Returns a random token.
  def User.new_token
    SecureRandom.urlsafe_base64
  end

  # Remembers a user in the database for use in persistent sessions.
  def remember
    self.remember_token = User.new_token
    update_attribute(:remember_digest, User.digest(remember_token))
  end

  # Returns true if the given token matches the digest.
  def authenticated?(remember_token)
    return false if remember_digest.nil?
    BCrypt::Password.new(remember_digest).is_password?(remember_token)
  end

  # Forgets a user.
  def forget
    update_attribute(:remember_digest, nil)
  end
end


从https://.com/a/41388844/5598043提到注入的答案

使用以下内容创建一个名为app / models / application_record.rb的新文件:

class ApplicationRecord <ActiveRecord :: Base self.abstract_class = true end





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