rails 校验大全(转载)
可以自定义validate(), 这个方法在每次保存数据时都会被调用.
如:
def validate
if name.blank? && email.blank?
errors.add_to_base("You must specify a name or an email address")
end
end
同时也可以自定义 validate_on_create(), validate_on_update()方法.
valid?()方法可以随时调用,用来测试数据是否能通过校验
返回的错误信息可用 error_messages_for(model)方法显示.
如:<%= error_messages_for 'article' %>
校验大全:
validates_acceptance_of
指定checkbox应该选中. (如:(*)我同意条款)
用法:validates_acceptance_of attr... [ options... ]
参数:message text 默认:“must be accepted.”
:on :save, :create, or :update
实例:
class Order < ActiveRecord::Base
validates_acceptance_of :terms,
:message => "Please accept the terms to proceed"
end
validates_associated
查验指定的object.
用法:validates_associated name... [ options... ]
参数:message text 默认: is “is invalid.”
:on :save, :create, or :update
实例:
class Order < ActiveRecord::Base
has_many :line_items
belongs_to :user
validates_associated :line_items,
:message => "are messed up"
validates_associated :user
end
validates_confirmation_of
数据重校
用法:validates_confirmation_of attr... [ options... ]
参数:message text 默认 “doesn’t match confirmation.”
:on :save, :create, or :update
实例:
对密码表:
<%= password_field "user", "password" %><br />
<%= password_field "user", "password_confirmation" %><br />
#第二表名为xxxx_confirmation
class User < ActiveRecord::Base
validates_confirmation_of :password
end
validates_each
使用block检验一个或一个以上参数.
用法:validates_each attr... [ options... ] { |model, attr, value| ... }
参数:allow_nil boolean 设为true时跳过nil对象.
:on :save, :create, or :update
实例:
class User < ActiveRecord::Base
validates_each :name, :email do |model, attr, value|
if value =~ /groucho|harpo|chico/i
model.errors.add(attr,"You can't be serious, #{value}")
end
end
end
validates_exclusion_of
确定被检对象不包括指定数据
用法:validates_exclusion_of attr..., :in => enum [ options... ]
#enum指一切可用include?()判断的范围.
参数:allow_nil 设为true将直接跳过nil对象.
:in (or :within) enumerable
:message text 默认为: “is not included in the list.”
:on :save, :create, or :update
实例:
class User < ActiveRecord::Base
validates_exclusion_of :genre,
:in => %w{ polka twostep foxtrot },
:message =>"no wild music allowed"
validates_exclusion_of :age,
:in => 13..19,
:message =>"cannot be a teenager"
end
validates_inclusion_of
确认对象包括在指定范围
用法:validates_inclusion_of attr..., :in => enum [ options... ]
参数:allow_nil 设为true直接跳过nil对象
:in (or :within) enumerable An enumerable object.
:message text 默认:“is not included in the list.”
:on :save, :create, or :update
实例:
class User < ActiveRecord::Base
validates_inclusion_of :gender,
:in => %w{ male female },
:message =>"should be 'male' or 'female'"
validates_inclusion_of :age,
:in => 0..130,
:message =>"should be between 0 and 130"
end
validates_format_of
用正则检验对象
用法:validates_format_of attr..., :with => regexp [ options... ]
参数:message text 默认为: “is invalid.”
:on :save, :create, or :update
:with 正则表达式
实例:
class User < ActiveRecord::Base
validates_format_of :length, :with => /^\d+(in|cm)/
end
validates_length_of
检查对象长度
用法:validates_length_of attr..., [ options... ]
参数:in (or :within) range
:is integer
:minimum integer
:maximum integer
:message text 默认文字会根据参数变动,可使用%d 取代确定的最大,最小或指定数据.
:on :save, :create, or :update
:too_long text 当使用了 :maximum后的 :message
:too_short text ( :minimum )
:wrong_length ( :is)
实例:
class User < ActiveRecord::Base
validates_length_of :name, :maximum => 50
validates_length_of :password, :in => 6..20
validates_length_of :address, :minimum => 10,
:message =>"seems too short"
end
validates_numericality_of
检验对象是否为数值
用法:validates_numericality_of attr... [ options... ]
参数:message text 默认 “is not a number.”
:on :save, :create, or :update
:only_integer
实例:
class User < ActiveRecord::Base
validates_numericality_of :height_in_meters
validates_numericality_of :age, :only_integer => true
end
validates_presence_of
检验对象是否为空
用法:validates_presence_of attr... [ options... ]
参数:message text 默认:“can’t be empty.”
:on :save, :create, or :update
实例:
class User < ActiveRecord::Base
validates_presence_of :name, :address
end
validates_uniqueness_of
检验对象是否不重复
用法:validates_uniqueness_of attr... [ options... ]
参数:message text 默认: “has already been taken.”
:on :save, :create, or :update
:scope attr 指定范围，用于组合校验
实例:
class User < ActiveRecord::Base
validates_uniqueness_of :name
end
class User < ActiveRecord::Base
validates_uniqueness_of :name, :scope =>"group_id"
end
#指定在同一group_id的条件下不重复.
常用正则:
E-Mail地址格式:
validates_format_of :email,
:with => /^([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})$/i,
:message => 'email must be valid'
网址格式:
validates_uri_existence_of :url, :with =>
/(^$)|(^(http|https)://[a-z0-9] ([-.]{1}[a-z0-9] )*.[a-z]{2,5}(([0-9]{1,5})?/.*)?$)/ix
Validation Helpers
有些确认是平常：这个属性必须不能为空，其它属性必须在18和65之间等等。“活动记录”有一套标准的帮助方法来添加这些确认给你的“模型”。每个都是类级别方法，所有名字都以validates_开头。每个方法接受可选的属性名字列表，它是由配置选项的哈希表提供给确认的。
例如，我们可以这样写先前确认
class User < ActiveRecord::Base
validates_format_of :name,
:with => /^w+$/,
:message => "is missing or invalid"
validates_uniqueness_of :name,
:on => :create,
:message => "is already being used"
end
大多数validates_methods接受:on和:message选项。:on选项确定何时应用确认并接受:save(缺省的)，:create，或:update中的一个。:message参数可以用生成错误消息覆写它。
确认失败时，帮助方法添加一个error对象给“活动记录”“模型”对象。这将被关联到被确认的字段。在确认之后，你可以查看“模型”对象的errors属性来访问错误列表。当“活动记录”被用做Rails应用程序一部分时，这个检查通常由两个步骤完成：
1、“控制器”试图保存一个“活动记录”对象，但因为确认的原因保存失败了 (返回false)。“控制器”将重新显示包含错误数据的表单。
2、“视图模板”使用error_messages_for()方法来显示“模型”对象的错误列表，并且用户有机会来修正字段。
http://sunac400.blog.163.com/blog/static/22658271200702243452435/
附加一段例子
class Product < ActiveRecord::Base
validates_presence_of :title,:description ,:image_url
validates_numericality_of :price
validates_uniqueness_of :title
validates_format_of :image_url,:with=>%r{\.(gif|jpg|png)$}i ,:message=>'must be a url for gif,jpg,png image.'
validates_length_of :title ,:minimum=>4,:maximum=>50,:message=>"title must be in 4~50."
validate:price_must_be_at_least_a_cent
protected
def price_must_be_at_least_a_cent
errors.add(:price,'should be at least 0.01') if price.nil?|| price<0.01
end
end
