displaying validation messages - what do i do in my form

Here's my form

<h1 id="school_name"><%=h @school.name %> (<%=h @school.place %>)</h1>

<h1 id="school_url"><%= link_to @school_url, @school.url %></h1>

<% form_for [@school, Review.new] do |f| %>

  <p>
  <%= f.label :first_name, "First Name" %><br />
  <%= f.text_field :first_name, :length => 40 %>
  </p>

  <p>
  <%= f.label :body, "Leave a review..." %><br />
  <%= f.text_area :body, :cols => 40, :rows => 6 %>
  </p>

  <p><%= f.submit "Add Review" %></p>

<% end %>

<% unless @school.reviews == [] %>

  <div id="reviews">
    <%= render :partial => @school.reviews %>
  </div>

<% end %>

so here's my reviews controller, i'd like to return to the schools show
action and show errors if the record not saved.

class ReviewsController < ApplicationController

  def create

    @school = School.find(params[:school_id])

    @review = @school.reviews.build(params[:review])

    if @review.save
      redirect_to @school
    else
      render :action => "new"
    end

  end

end

I'd like to show validation errors in the initial form, so how do I do
the line...

<% form_for [@school, Review.new] do |f| %>

You don't want Review.new. You want to use the instance of review that
had the errors on it. This will also means that the text boxes etc.
will be filled with what the user typed in before. You can use
f.error_messages_for to display the errors or you can roll your own
thing if you don't like the output that generates but the key thing is
that you need to use th instance which has errors on it.

Fred

But this doesn't work for me..

<% form_for [@school, @review.new] do |f| %>

Your form_for should be using @school, @review.

In the controller new method, just like you do a (I hope)
  @school = School.new
do a
  @review = Review.new

OK, kind of got you...appreciate i need the instance with the errors
in
it, how do i achieve that?

so not this...

<% form_for [@school, Review.new] do |f| %>

But this doesn't work for me..

<% form_for [@school, @review.new] do |f| %>

if @review is the object with your errors you don't need to call new -
just @review will do

Fred

ok thanks fred... but...

class ReviewsController < ApplicationController

  def create

    @school = School.find(params[:school_id])

    @review = @school.reviews.build(params[:review])

    if @review.save
      redirect_to @school
    else
      # what goes here ???
    end

  end

end

exactly what you had before - just render your 'new' action

Fred

i don't have a new action or view in my reviews controller...

my comments are being entered and displayed on the schools show page.

then pass whatever you need to pass to render to get it to render the
form again. You know where that file is, I don't

Fred

Arrrr! I see...sorry being dopey, just enhance the render command - I
read you can do this elesewhere...

BUT, It still deosnt work!

class ReviewsController < ApplicationController

  def create

    @school = School.find(params[:school_id])

    @review = @school.reviews.build(params[:review])

    if @review.save
      redirect_to @school
    else
      render :action => "show", :controller => "schools" # here....!!!!
    end

  end

end

===== it's trying to go here...

Showing app/views/reviews/show.html.erb where line #42 raised:
undefined method `edit_review_path' for #<ActionView::Base:0x21c2260>

It should go back to here I suppose...

http://localhost:3000/schools/2

Arrrr! I see...sorry being dopey, just enhance the render command - I
read you can do this elesewhere...

which bit of the view is causing this ?

Fred