Question

说我有两个班级

class User
  attr_accessible :name

  has_one :address

  validates :name, :presence => true
  validates_associated :address
end

class Address
  attr_accessible :country, :user_id

  belongs_to :user

  validates :country, :presence => true
  validates :user, :presence => true
end

现在当我尝试创建无效的Address时，它失败了（这很好）

a = Address.new
a.valid?  #=> false

但是当我使用无效Address构建用户时，它会通过（这是不好的）

u = User.first
u.build_address

u.valid?  #=> true
u.save    #=> true

由于此User已Address与country =＆gt;为零。

如果Rails无效，我如何告诉Rails不保存Address？

修复：我通过在代码中添加跟随行来修复此问题。谢谢大家。

validates_associated :address, :if => :address

Answer 1

class User
  attr_accessible :name

  has_one :address, :validate => true

  validates :name, :presence => true
  validates_associated :address

端

Answer 2

您还需要确认Address实际存在User：

class User < ActiveRecord::Base
  validates :address, :associated => true, :presence => true
end

有了这个，我得到：

>> u = User.first
=> #<User id: 1, name: "Bob", created_at: "2013-10-09 15:17:21", updated_at: "2013-10-09 15:17:21">
>> u.build_address
=> #<Address id: nil, user_id: 1, country: nil, created_at: nil, updated_at: nil>
>> u.valid?
=> false
>> u.errors
=> #<ActiveModel::Errors:0x007fe1d6919b18 @base=#<User id: 1, name: "Bob", created_at: "2013-10-09 15:17:21", updated_at: "2013-10-09 15:17:21">, @messages={:address=>["is invalid"]}>
>> u.address.errors
=> #<ActiveModel::Errors:0x007fe1d69197a8 @base=#<Address id: nil, user_id: 1, country: nil, created_at: nil, updated_at: nil>, @messages={:country=>["can't be blank"]}>

保存父对象时如何确保子对象有效？

2 个答案: