Question

通过外键链接rails对象的最佳方法是什么？这是我的例子。从业者有一张考勤卡（每天收集工作时数）。我想把这位从业者的身份证明在约会上来表明：

来自routes.rb

  resources :locations do
    resources :practitioners, only: [:new, :create]
  end

  resources :practitioners, except: [:new, :create] do
    resources :timecards, except: :delete
    resources :appointments
  end

timecard.rb - 你可以在这里看到我强迫timecard.practitioner_id为3，但那是一次蛮力测试。

class Timecard < ActiveRecord::Base
  belongs_to :practitioner
 attr_protected :id

  before_save :set_practitioner_id

  def set_practitioner_id
    if self.practitioner_id.blank?
      self.practitioner_id = 3
    end
  end
end

从我的控制器......

def create
    @practitioner = Practitioner.find(params[:practitioner_id])
    @timecard = Timecard.create(params[:timecard])


    respond_to do |format|
      if @timecard.save
        format.html { redirect_to @practitioner, notice: 'Timecard was successfully created.' }
        format.json { render json: @timecard, status: :created, location: @timecard }
      else
        format.html { render action: "new" }
        format.json { render json: @timecard.errors, status: :unprocessable_entity }
      end
    end
  end

我可以看到Practer_id = 3的参数（这是我想要使用的），我只是不知道如何在代码中访问它。

Parameters:

{"utf8"=>"✓",
 "authenticity_token"=>"DIp4R31McXnBNP4NB06KDTzV+8lLcWvxbq1w9J+Z1+M=",
 "timecard"=>{
   "hours_worked"=>"2",
   "activity_date(1i)"=>"2013",
   "activity_date(2i)"=>"3",
   "activity_date(3i)"=>"20",
   "practitioner_id"=>"",
   "location_id"=>"1"
 },
 "commit"=>"Create Timecard",
 "practitioner_id"=>"3"   <== this is what I want to use
}

Answer 1

如果我理解您的问题，您可以在将时间卡保存在控制器中之前设置@timecard.practitioner = @practitioner。您可以这样做，因为belongs_to gives you一个practioner=方法“分配关联对象，提取主键，并将其设置为外键。”

Answer 2

我假设一个从业者有很多时间卡，所以你应该可以做类似的事情

# practitioner.rb
has_many :timecards

# controller
@practitioner = Practitioner.find(params[:practitioner_id])
@timecard = @practitioner.timecards.build(params[:timecard])

设置关联将负责为您设置外键。

通过外键链接rails对象

2 个答案: