Question

我有项目和用户通过has_many加入：通过称为所有权的连接模型。每个所有权都有我想要访问的owner_type属性。

我希望有办法将user_id传递给项目模型，并通过所有权连接模型获取owner_type。反之亦然我想将project_id传递给用户模型并通过所有权连接模型获取owner_type。这就是我所拥有的：

class Project < ActiveRecord::Base
  attr_accessible :name, :description

  has_many :ownerships
  has_many :users, :through => :ownerships

  validates :name, :presence => true,
                   :length => { :maximum => 50 }

  def owner_type?(user_id)
    @user_id = user_id
    @ownership = self.ownerships.where(:user_id => @user_id)
    @ownership.owner_type
  end

end

class User < ActiveRecord::Base
  attr_accessible :name, :email, :admin

  has_many :ownerships
  has_many :projects, :through => :ownerships

  accepts_nested_attributes_for :projects

  email_regex = /\A[\w+\-.]+@[a-z\d\-.]+\.[a-z]+\z/i

  validates :name, :presence => true,
                   :length => { :maximum => 50 }

  #validates :email, :presence => true,
  #                  :format => { :with => email_regex },
  #                  :uniqueness => { :case_sensitive => false }

  validates_inclusion_of :admin, :in => [true, false]

  def self.create_with_omniauth(auth)
    create! do |user|
      user.provider = auth["provider"]
      user.uid = auth["uid"]
      user.name = auth["user_info"]["name"]
      user.admin = false
    end
  end
end

class Ownership < ActiveRecord::Base
  attr_accessible :owner_type

  belongs_to :project
  belongs_to :user

  validates :user_id, :presence => true

  validates :project_id, :presence => true

  validates :owner_type, :presence => true

end

然后在我的项目#show page：

<%= @project.owner_type?(current_user.id) %>

我做错了什么？如何从任何位置访问所有权模型中的owner_type属性？它永远不会奏效。

Answer 1

您尚未粘贴实际的错误。但这就是我认为出了问题。

ownerships是一种has_many关系。它将始终返回一组结果。因此，@ownership = self.ownerships.where(:user_id => @user_id)将返回一个数组。因此，如果您只期望1个结果，那么您应该这样做。

@ownership = ownerships.where(:user_id => @user_id).first
@ownership.owner_type

这应该有用。

尝试从连接模型中读取属性时不会出现方法错误

1 个答案: