Question

im not able to display the validation error, even though it is validating the form.
In my partial form

• if @post.errors.any?

seems to be the problem, the @post returns a false for error and so no error is displayed.
but the @comment returns a true for error, but im not able to replace @post with @comment since it throws an undefined ‘comment’ error..

my partial form which is begin called inside the show:

%html
%head
%title= @post.title
  %body
    %h2 Create Comments:
    = form_for([@post, @post.comments.build]) do |f|
      - if @post.errors.any?                # <--- Unsure what to do here..
        #error_explanation
        %h2
          = pluralize(@post.errors.count, "error")
          prohibited this cart from being saved:
        %ul
          - @post.errors.full_messages.each do |msg|
            %li= msg
    = f.label :Name
    %br
    = f.text_field :name 
    %br
    %br
    = f.label :Text
    %br
    = f.text_area :text
   %br
   %br
   = f.submit 

my comments controller:

def create
@post = Post.find(params[:post_id])

@comment = @post.comments.build(params[:comment])
   respond_to do |format| 
if @comment.save
    format.html { redirect_to @post }
else
    format.html { redirect_to @post }
end
   end
 end

this is show page from which im rendering the file:

%html
%head
  %title= @post.title
%body
  %strong Author name:
  = @post.author_name
  %br
  %br
  %strong Title:
  = @post.title
  %br
  %br
  %strong Email:
  = @post.email
  %br
  %br
  %strong Description:
  = @post.description

  %h2 Comments for this Post:

  = render :partial => @post.comments

  = render :partial => "comments/form"

Answer 1

You can use validates_associated on your post model to check for validation errors on your associated model.