Testing for the presence of a variable in Ruby on Rails

Question

After creating new entries this code works:

<%= book.title, :class=>"test" %>

But when database empty its throws error is there any way to display if its empty don't show else show?

similar like this:

<% if ... empty
<p>no record found</p>
<% else %>
<%= book.title, :class=>"test" %>
<% end %>

thanks!

Answer 1

<% if book.blank? %>
  <p>no record found</p>
<% else %>
  <%= book.title, :class=>"test" %>
<% end %>

Answer 2

The try method will allow you to work with an object that may be nil without throwing an exception if it actually is nil. If book is nil then try will return nil and the || will consider that falsy and will use the right side ("no record found"). Note that this will simply treat "no record found" as though it was the title. If that's ok you can try something like this:

<%= book.try(:title) || "no record found", :class => "test" %>