在使用accepts_nested_attributes_for时，如何设置将拒绝现有记录的过滤器

Question

I have a Message and Source model related as follows:

class Message < ActiveRecord::Base
  has_many :sources
  accepts_nested_attributes_for :sources, :allow_destroy => true, :reject_if => proc{|s| s[:href].blank?}
end

class Source < ActiveRecord::Base
  belongs_to :outgoing_message
  validates_presence_of :href
end

When I submit my form (built using form_for and fields_for ) it filters out any new sources with blank hrefs. But what I want is for it to delete any existing sources whose hrefs have been set to blank. Is there a simple way to do that?

Answer 1

Hi Inside your Message model you may add validates_associated :sources If you need clear all Message records with blank :href from your database before saving new ones then inside your controller you may write

before_filter :some_filter, :only=>[:form_action]
...
def some_filter 
  Source.delete_all("href = '' OR href IS NULL")
end