小编Aar*_*man的帖子

validates :presence和之间有什么区别validates_presence_of？通过ActiveModel它看起来他们以相同的方式设置验证.但是,给定以下模型定义:

class Account < ActiveRecord::Base
  has_one :owner_permission, :class_name => 'AccountPermission', :conditions => { :owner => true, :admin => true }
  has_one :owner, :class_name => 'User', :through => :owner_permission, :source => :user

  validate :owner, :presence => true
  validates_associated :owner
end

在实例上调用save Account不会验证所有者的存在.但是,如果我使用validates_presence_of它会.