Question

我有物业，居民和人民的模型（城外人士，所以不得不是居民）然后我有所有者加入我设置的表，如果财产属于居民或人

这是我的模特

class Property < ActiveRecord::Base
    has_many :owners, dependent: :destroy
    has_many :residents, through: :owners
    has_many :people, through: :owners
    belongs_to :ptype
end

class Resident < ActiveRecord::Base
    has_many :owners, dependent: :destroy 
    has_many :properties, through: :owners
end

class Person < ActiveRecord::Base
    has_many :owners, dependent: :destroy 
    has_many :properties, through: :owners
end

class Owner < ActiveRecord::Base
    belongs_to :resident
    belongs_to :property
    belongs_to :person
end

我希望查看显示关系的位置，以便owner.resident显示属性或者owner.person显示属性

 <% if @owner.resident %>
  <ol><% @residents.properties.each do |property| %>
            <li><%= property.ptype.name %> , <%= property.address %></li>
          <% end %> 
</ol>
<% end %>

<% if @owner.person %>
<ol><% @people.properties.each do |property| %>
            <li><%= property.ptype.name %> , <%= property.address %></li>
            <% end %> 
</ol><% end %>

当我想显示所有者是居民的关系时，我得到错误没有方法属性nil：class for @people当我想显示关系所有者是一个人我得到了oposite，错误没有方法属性为nil ：@residents的课程

我明白这是因为它没有返回记录，但这就是为什么我把它放在那里

我做错了什么？

编辑：我使用rails生成的默认控制器

class PeopleController < ApplicationController
  before_action :set_person, only: [:show, :edit, :update, :destroy]

  def index
    @people = Person.all
  end

  def show
  end

  def new
    @person = Person.new
  end

  def edit
  end

  def create
    @person = Person.new(person_params)
    respond_to do |format|
      if @person.save
        format.html { redirect_to @person, notice: 'Person was successfully created.' }
        format.json { render :show, status: :created, location: @person }
      else
        format.html { render :new }
        format.json { render json: @person.errors, status: :unprocessable_entity }
      end
    end
  end

  def update
    respond_to do |format|
      if @person.update(person_params)
        format.html { redirect_to @person, notice: 'Person was successfully updated.' }
        format.json { render :show, status: :ok, location: @person }
      else
        format.html { render :edit }
        format.json { render json: @person.errors, status: :unprocessable_entity }
      end
    end
  end

  def destroy
    @person.destroy
    respond_to do |format|
      format.html { redirect_to people_url, notice: 'Person was successfully destroyed.' }
      format.json { head :no_content }
    end
  end
  private

    def set_person
      @person = Person.find(params[:id])
    end

    def person_params
      params.require(:person).permit(:name, :email, :tel)
    end
end

class ResidentsController < ApplicationController
  before_action :set_resident, only: [:show, :edit, :update, :destroy]
  def index
    @residents = Resident.all
  end

  def show
    @residents = Resident.find(params[:id])
  end

  def new
    @resident = Resident.new
  end

  def edit
  end

  def create
    @resident = Resident.new(resident_params)
    respond_to do |format|
      if @resident.save
        format.html { redirect_to @resident, notice: 'Záznam bol úspešne vytvorený.' }
        format.json { render :show, status: :created, location: @resident }
      else
        format.html { render :new }
        format.json { render json: @resident.errors, status: :unprocessable_entity }
      end
    end
  end

  def update
    respond_to do |format|
      if @resident.update(resident_params)
        format.html { redirect_to @resident, notice: 'Záznam bol úspešne upravený.' }
        format.json { render :show, status: :ok, location: @resident }
      else
        format.html { render :edit }
        format.json { render json: @resident.errors, status: :unprocessable_entity }
      end
    end
  end

  def destroy
    @resident.destroy
    respond_to do |format|
      format.html { redirect_to residents_url, notice: 'Záznam bol úspešne zmazaný.' }
      format.json { head :no_content }
    end
  end
  private

    def set_resident
      @resident = Resident.find(params[:id])
    end
    def resident_params
      params.require(:resident).permit(:name, :birthdate, :birthId, :address, :email, :tel)
    end
end

Answer 1

好吧，我从开始就做错了这是一个解决方案

<% if @owner.resident.present? %>
  <ol><% @owner.resident.properties.each do |property| %>
            <li><%= property.ptype.name %> , <%= property.address %></li>
          <% end %> 
</ol>
<% end %>
<% if @owner.person.present? %>
<ol><% @owner.person.properties.each do |property| %>
            <li><%= property.ptype.name %> , <%= property.address %></li>
          <% end %> 
</ol>
<% end %>

Answer 2

IIRC @owner.person和@owner.resident将返回代理对象，直到完成某些操作 - 尝试@owner.person.present?和@owner.resident.present?

rails has_many通过多个模型 - 没有nil：class的方法

2 个答案: