在Rails中创建后关联两个记录

其中@user是最近创建的用户,@person是现有用户。

@user.person = @person
@user.save

或者:

User.new :person => @person, ... #other attributes

或参数形式:

User.new(params[:user].merge({person => @person}))

就形式而言:

<% form_for @user do |f| %>
  ...
  <% fields_for :person do |p| %>
    <%= p.collection_select, :id, Person.all,  :id, :name, :include_blank => "Use fields to create a person"%>
    <%= p.label_for :name%>
    <%= p.text_field :name %>
    ...
  <% end %>
<% end %>

在用户控制器中:

def create
  @user = User.create(params[:user])
  @person = nil
  if params[:person][:id]
    @person = Person.find(params[:person][:id])
  else
    @person = Person.create(params[:person])
  end
  @user.person = @person
  ...
end

如果不想为此创建/更改表单,可以这样做

@person_instance.user = @user_instance

因为有很多关系,它是:

@person_instance.users << @user_instance

首先必须执行嵌套表单:

<% form_for @user do |user| %>
  <%= user.text_field :name %>
  <% user.fields_for user.person do |person| %>
    <%= person.text_field :name %>
  <% end %>
  <%= submit_tag %>
<% end %>

在您的用户模型中:

class User < ActiveRecord::Base
  accepts_nested_attributes_for :person
end

如果希望在用户为以下用户时删除该用户:

class User < ActiveRecord::Base
  accepts_nested_attributes_for :person, :allow_destroy => true
end

在你的控制器里什么也不做:

class UserController < ApplicationController
  def new
    @user = User.new
    #find the person you need
    @user.person = Person.find(:first)
  end

  def create
    @user = User.new(params[:user])
    @user.save ? redirect_to(user_path(@user)) : render(:action => :new)
  end
end