我正在创建一个示例项目，但是当我尝试创建一个新帖子时出现错误“为 nil 类创建未定义的方法”
我的代码如下。
用户.rb
class User < ActiveRecord::Base
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :trackable, :validatable
has_one :post, dependent: :destroy
end
post.rb
class Post < ActiveRecord::Base
belongs_to :user
end
post_controller.rb
class PostsController < ApplicationController
def create
@user = current_user
if @user.post.blank?
@post = @user.post.create(params[:post].permit(:title, :text))
end
redirect_to user_root_path
end
end
新的.html.erb
<%= form_for([current_user, current_user.build_post]) do |f| %>
<p>
<%= f.label :title %><br>
<%= f.text_field :title %>
</p>
<p>
<%= f.label :text %><br>
<%= f.text_area :text %>
</p>
<p>
<%= f.submit %>
</p>
<% end %>
但是在尝试了很多次之后，我做了一些改变，它开始工作了，但我不知道这两个代码之间有什么区别。
用户.rb
class User < ActiveRecord::Base
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :trackable, :validatable
has_many :posts, dependent: :destroy
end
post.rb
class Post < ActiveRecord::Base
belongs_to :user
end
post_controller.rb
class PostsController < ApplicationController
def create
@user = current_user
if @user.posts.blank?
@post = @user.posts.create(params[:post].permit(:title, :text))
end
redirect_to user_root_path
end
end
新的.html.erb
<%= form_for([current_user, current_user.posts.build]) do |f| %>
<p>
<%= f.label :title %><br>
<%= f.text_field :title %>
</p>
<p>
<%= f.label :text %><br>
<%= f.text_area :text %>
</p>
<p>
<%= f.submit %>
</p>
<% end %>
我的 routes.rb 是
UserBlog::Application.routes.draw do
devise_for :users, controllers: { registrations: "registrations" }
resources :users do
resources :posts
end
# You can have the root of your site routed with "root"
root 'home#index'
end
请帮助我并告诉我这两个代码有什么区别？