form_for，未定义的方法名称

Question

我想在我的rails项目中添加一个注释模型，但我在渲染页面中遇到错误：

错误：

Showing /Users/sovanlandy/rails_projects/sample_app/app/views/shared/_comment_form.html.erb where line #4 raised:

undefined method `comment_content' for #<Comment:0x007fd0aa5335b8>

。以下是相关代码

comment.rb

class Comment < ActiveRecord::Base
attr_accessible :comment_content

belongs_to :user
belongs_to :micropost

validates :comment_content, presence: true
validates :user_id, presence: true
validates :micropost_id, presence: true  
end

micropost.rb

class Micropost < ActiveRecord::Base
attr_accessible :content
belongs_to :user
has_many :comments, dependent: :destroy
.....
end

user.rb

class User < ActiveRecord::Base
 has_many :microposts, dependent: :destroy
has_many :comments
....
end

comments_controller.rb

class CommentsController < ApplicationController

 def create
@micropost = Micropost.find(params[:micropost_id])
@comment = @micropost.comments.build(params[:comment])
@comment.micropost = @micropost
@comment.user = current_user

if @comment.save
   flash[:success] = "Comment created!"z
   redirect_to current_user
else
  render 'shared/_comment_form'
end
end

end

_comment_form_html.erb

的部分内容

<%= form_for([micropost, @comment]) do |f| %>
<%= render 'shared/error_messages', object: f.object %>
 <div class="field">
  <%= f.text_field :comment_content, place_holder: "Comment" %>
 </div>
  <button class="btn" type="submit">
   Create
 </button>
 <% end %>

我从_micropost.html.erb类中调用了patial _comment_form.html.erb

     <%= render 'shared/comment_form', micropost: micropost %>

我还将注释作为嵌套资源放在route.rb

中

  resources :microposts do
    resources :comments
  end

如何解决错误？ 谢谢！

Answer 1

您是否为评论创建了相应的迁移？该错误表明它正在尝试访问不存在的方法。这意味着您错误地写了该字段的名称，或者您没有运行将该字段添加到模型的迁移。你能从schema.rb复制评论表的部分吗？

Answer 2

在micropost.rb写

中尝试此操作

class Micropost < ActiveRecord::Base
  ...
  has_many :comments, dependent: :destroy
  accepts_nested_attributes_for :comments
  attr_accessible :comments_attributes
  ...
end

并在_comment_form.html.erb

中

<%= form_for @micropost do |f| %>
  <%= f.fields_for :comments do |comment| %>
      ...
      <div class="field>
          <%= comment.text_field :comment_content, place_holder: "Comment" %>
      </div>
      ...
  <% end %>
  <%= f.submit%>
<% end %>