问题

I want to add a comment model to my rails project but i got error in the render page saying:

error:

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>

. Here are the related code

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

Partial of _comment_form_html.erb

<%= 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 %>

I called the patial _comment_form.html.erb from _micropost.html.erb class

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

I also put comment as nested resource in route.rb

  resources :microposts do
    resources :comments
  end

How to resolve the error? Thanks!

回答1:

Did you create the corresponding migrations for Comment a ran it? The error says that it's trying to access a method that don't exist. That means that you write wrong the name of the field or that you did not run the migrations that adds that field to your model. Could you copy the section of comments table from schema.rb?

回答2:

try this in your micropost.rb write

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

and in your _comment_form.html.erb

<%= 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 %>

来源：https://stackoverflow.com/questions/12985940/form-for-undefined-method-name

标签

ruby-on-rails

ruby

form-for

form_for , undefined method name

问题