访问父对象属性的“rails方式”是什么？

Let's say I have a model Doctor, and a model Patient. A Patient belongs_to a Doctor.

假设我有模特医生和模特病人。病人属于医生。

A Doctor has an attribute office.

医生有一个属性办公室。

I would want to, given a Patient p, be able to say p.office and access the office of p's Doctor.

我想,如果有患者p,可以说p.office并访问p's Doctor的办公室。

I could always write a method

我总是可以写一个方法

class Patient
    belongs_to :doctor
    def office
        self.doctor.office
    end

But is there a more automatic way to expose all of the Doctor's attribute methods to the Patient? Perhaps using method_missing to have some kind of catch-all method?

但有没有更自动的方式将所有Doctor的属性方法暴露给患者?也许使用method_missing来拥有某种catch-all方法?

2 个解决方案

#1

You could use delegate.

你可以使用委托。

class Patient
    belongs_to :doctor
    delegate :office, :to => :doctor
end

You could have multiple attributes in one delegate method.

您可以在一个委托方法中拥有多个属性。

class Patient
    belongs_to :doctor
    delegate :office, :address, :to => :doctor
end

#2

I believe you are talking about using Patient as a delegator for Doctor.

我相信你在谈论使用Patient作为Doctor的委托人。

class Patient < ActiveRecord::Base
  belong_to :doctor

  delegate :office, :some_other_attribute, :to => :doctor
end

I think this would be the method_missing way of doing this:

我认为这将是method_missing方式:

def method_missing(method, *args)
  return doctor.send(method,*args) if doctor.respond_to?(method)
  super
end

#1