Ruby-on-rails – Error message in Ruby on Rails

<%= form_for(@model) do |f| %>
 <% if @model.errors.any? %>
 < div id="error_explanation">
 
<%= pluralize(@model.errors.count, "error") %> prohibited this model from being saved:


 

 <% @model.errors.full_messages.each do |msg| %>
 
<%= msg %>

 <% end %> 
 

 

I implemented the validates_presence_of field for the comments in the guide. How to display validation errors on the post page. I know the rendering, but there is rendering. I need to send all the variables I use on the post page. Am I right?

I don’t believe that plugins are necessary. The scaffolding generator in Rails 3.x does this:

<%= form_for(@model) do |f| %>
 <% if @model.errors.any? %>
 

 < h2><%= pluralize(@model.errors.count, "error") %> prohibited this model from being saved:

 

 <% @model .errors.full_messages.each do |msg| %>
 
<%= msg %>

 <% end %>
 

 

 <% end %>
<%# Rest of form... %>