验证前自动清除模型属性的空格

validates_presence_of时，如果属性中有空格，就不管用了。

在进行验证时，一般都需要trim（ruby是strip）后再验证，但是ror的验证并没有象struts2一样提供先trim再验证的接口，还好有一个插件可以自动清除属性两边的空格。

http://github.com/rmm5t/strip_attributes/tree/master

 

StripAttributes

StripAttributes is a Rails plugin that automatically strips all ActiveRecord model attributes of leading and trailing whitespace before validation. If the attribute is blank, it strips the value to nil .

It works by adding a before_validation hook to the record. By default, all attributes are stripped of whitespace, but :only and :except options can be used to limit which attributes are stripped. Both options accept a single attribute (:only => :field ) or arrays of attributes (:except => [:field1, :field2, :field3] ).

Examples

  class DrunkPokerPlayer < ActiveRecord::Base
    strip_attributes!
  end

  class SoberPokerPlayer < ActiveRecord::Base
    strip_attributes! :except => :boxers
  end

  class ConservativePokerPlayer < ActiveRecord::Base
    strip_attributes! :only => [:shoe, :sock, :glove]
  end

Installation

Option 1. Use the standard Rails plugin install (assuming Rails 2.1).

  ./script/plugin install git://github.com/rmm5t/strip_attributes.git

Option 2. Use git submodules

  git submodule add git://github.com/rmm5t/strip_attributes.git vendor/plugins/strip_attributes

Option 3. Use braid (assuming you’re using git)

  braid add --rails_plugin git://github.com/rmm5t/strip_attributes.git
  git merge braid/track

Other

If you want to use this outside of Rails, extend StripAttributes in your ActiveRecord model after putting strip_attributes in your $LOAD_PATH :

  require 'strip_attributes'
  class SomeModel < ActiveRecord::Base
    extend StripAttributes
    strip_attributes!
  end