Error messages and display in Ruby on Rails - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to display error messages for a model in a Rails view.

Ruby on Rails

<% if @user.errors.any? %>
  <div id="error_explanation">
    <h2>[1] errors prohibited this user from being saved:</h2>
  </div>
<% end %>

Drag options to blanks, or click blank then click option'

A<%= pluralize(@user.errors.count, "error") %>

B<%= @user.errors.full_messages %>

C<%= @user.errors.count %>

D<%= @user.errors.messages %>

Attempts:

3 left

💡 Hint

Common Mistakes

Using @user.errors.full_messages directly in the header instead of the count.

Forgetting to pluralize the word 'error'.

Using @user.errors.messages which is a hash, not a string.

The pluralize helper formats the error count with correct singular/plural form, which is standard in Rails error displays.

2fill in blank

medium

Complete the code to list all error messages for a model in a Rails view.

Ruby on Rails

<ul>
  <% @user.errors.full_messages.each do |message| %>
    <li>[1]</li>
  <% end %>
</ul>

Drag options to blanks, or click blank then click option'

Amessage.full

Bmessage.to_s

[e-mail]_messages

Dmessage

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to call methods on 'message' which is already a string.

Using @user.errors.full_messages inside the loop instead of the loop variable.

Inside the loop, 'message' is a string representing one error message, so just output 'message'.

3fill in blank

hard

Fix the error in the code to correctly display error messages for a model in a Rails view.

Ruby on Rails

<% if @post.errors.any? %>
  <div id="error_explanation">
    <h2>[1] errors prevented this post from saving:</h2>
    <ul>
      <% @post.errors.full_messages.each do |msg| %>
        <li><%= msg %></li>
      <% end %>
    </ul>
  </div>
<% end %>

Drag options to blanks, or click blank then click option'

A<%= pluralize(@post.errors.count, "error") %>

B<%= @post.errors.count %>

C<%= @post.errors.full_messages.count %>

D<%= @post.errors.messages.count %>

Attempts:

3 left

💡 Hint

Common Mistakes

Using count alone without pluralize, which shows just a number without the word.

Using full_messages.count which is the same as errors.count but missing pluralize formatting.

The pluralize helper formats the error count with correct singular/plural form, which is the correct way to show error count in Rails.

4fill in blank

hard

Fill both blanks to create a Rails helper method that returns formatted error messages for a model.

Ruby on Rails

def formatted_errors(model)
  return "" if model.errors.empty?
  messages = model.errors.full_messages.map { |msg| "<li>[1]</li>" }.join
  "<ul>[2]</ul>".html_safe
end

Drag options to blanks, or click blank then click option'

Amsg

Bmessages

Cmsg.html_safe

Dmodel.errors.full_messages

Attempts:

3 left

💡 Hint

Common Mistakes

Using model.errors.full_messages directly inside the map block instead of 'msg'.

Putting the entire messages string inside each

instead of joining after mapping.

Inside map, use 'msg' to insert each message. Then wrap all messages in

tags using the 'messages' string.

5fill in blank

hard

Fill all three blanks to display error messages with a heading and list in a Rails view partial.

Ruby on Rails

<% if [1].errors.any? %>
  <div id="error_explanation">
    <h2>[2] errors prohibited this [3] from being saved:</h2>
    <ul>
      <% [1].errors.full_messages.each do |message| %>
        <li><%= message %></li>
      <% end %>
    </ul>
  </div>
<% end %>

Drag options to blanks, or click blank then click option'

A@article

B<%= pluralize(@article.errors.count, "error") %>

Carticle

D@comment

Attempts:

3 left

💡 Hint

Common Mistakes

Using different variable names inconsistently.

Not pluralizing the error count in the heading.

Using instance variable syntax inside the heading string.

Use '@article' as the model variable, pluralize the error count for the heading, and use 'article' as the model name in the message.