手把手教你学习ROR-5.Validation

Rails应用一般有三层校验

1 在Client端，可以使用JQuery-Validation 框架

2 在Controller端，配置Model时的validate，会在Controller调用save，update之前进行校验

• create
• create!
• save
• save!
• update
• update!

3 Database,在schema中设置

A 校验方法

1 校验存在性

validates :email,:password, presence: true

2 校验字段长度

validates :nickname, length: { minimum: 2,maximum:20}

3 验证唯一性

validates :email, uniqueness: true

4 校验格式

validates :email, format: { with:/@/}

5 校验是否为数字

validates :user_id, numericality: { only_integer: true }

6 验证字段是否不存在，string是否为空或者为“”，可以用present校验这个字段

validates :name, :login, :email, absence: true

7 验证某个字段是否在集合内

 validates :size, inclusion: { in: %w(small medium large), message: "%{value} is not a valid size"}

8 验证某个字段不在集合内

validates :domain, exclusion: { in: %w(www us ca jp), message: "Subdomain %{value} is reserved."}

9 用自己的Valiator类来进行校验

validates_with GoodnessValidator, fields: [:first_name, :last_name]

10 需要确认confirmation进行校验

 validates :email, confirmation: true

B 其他字段

1allow_nil

validates :sex, inclusion: { in: %w(boy girl), message: "%{value} is not a sex type" },allow_nil: true

2 allow_blank

validates :sex, inclusion: { in: %w(boy girl), message: "%{value} is not a sex type" },allow_blank: true

3 message

validates :sex, inclusion: { in: %w(boy girl), message: "%{value} is not a sex type" },allow_nil: true

4 on

validates :email, uniqueness: true, on: :create

5 strict（可以自己定制Exception，当validate不通过时，raise Exception）

validates :token, presence: true, uniqueness: true, strict: TokenGenerationException

6 if

validates :surname, presence: true, if: "name.nil?"

7 unless

validates :surname, presence: true, unless: "name.nil?"

C Validation in the view

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

<ul>
<% @post.errors.full_messages.each do |msg| %>
<li><%= msg %></li>
<% end %>
</ul>
</div>
<% end %>