084-rails-form-validation

[happypeter]

irb(main):006:0> u.errors.messages[:name]
=> ["can't be blank"]
irb(main):007:0> u.errors[:name]
=> ["can't be blank"]

[happypeter]

判断有无该项错误：

irb(main):008:0> u.errors[:name].any?
=> true

[happypeter]

Furthermore, if you use the Rails form helpers to generate your forms, when a validation error occurs on a field, it will generate an extra

around the entry.

<div class="field_with_errors">
 <input id="post_title" name="post[title]" size="30" type="text" value="">
</div>

http://guides.rubyonrails.org/active_record_validations.html#displaying-validation-errors-in-views

[happypeter]

如果要在视频中重复一遍 http://railscasts.com/episodes/250-authentication-from-scratch-revised 中的内容就太多了

我主要想讲的内容：

• add proper validation, customize validator
• nicer error msg in view
• i18n for the msg

[happypeter]

error message i18n

以开始想用投机取巧的方法，绕过 i18n，所以用了很多：

 validates_presence_of :name, :message => "不能为空"
  validates_uniqueness_of :name, :case_sensitive => false, :message => "已被占用"
  validates_presence_of :email, :message => "不能为空"
  validates_uniqueness_of :email, :case_sensitive => false, :message => "已被占用"

也就是直接给出中文报错信息作为参数。但是有些错误就不知道怎么传入中文 error 了，例如来自 has_secure_password 给出的相关报错 does not march confirmation。

所以还是走一下正规流程吧： http://guides.rubyonrails.org/i18n.html#translations-for-active-record-models http://stackoverflow.com/questions/808547/fully-custom-validation-error-message-with-rails

好在只要把 application.rb 中加入

config.i18n.default_locale = 'zh-CN'

报错信息就会显示为：translation missing: zh-CN.activerecord.errors.models.user.attributes.password.confirmation

[happypeter]

show notes

• Code

rails new baby -d mysql

application.rb

    config.generators do |g|
        g.assets false
        g.helper false
        g.test_framework false
    end

rake db:create;rake db:migrate
rails g model user name:string email:string password_digest:string token:string
rake db:migrate
rails g controller users welcome signup login

route.rb

Signup::Application.routes.draw do
  root to: "users#welcome"
  get "login" => "users#login", :as => "login"
  get "signup" => "users#signup", :as => "signup"
  post "create_login_session" => "users#create_login_session"
  delete "logout" => "users#logout", :as => "logout"
  resources :users, only: [:create]
end

rm public/index.html.erb
rails s

[happypeter]

http://happycasts.net/episodes/84

done