Ruby on Rails 学习笔记 - 2 Toy

1. 生成一个User的Model

 

例1

rails generate scaffold User name:string email:string

生成的Model除了有name, email还有一个Integer的Id。

例2

rails generate scaffold Micropost content:text user_id:integer

 

2. 迁移(migrate)数据库

bundle exec rake db:migrate

3. 流程图

4. 验证(validate)

class Micropost < ActiveRecord::Base
  belongs_to :user
  validates :content, length: { maximum: 140 },
                              presence: true
end

class User < ActiveRecord::Base
  has_many :microposts
  validates :name, presence: true
  validates :email, presence: true
end

 

5. Console

rails console