Ruby/Rails Conditional search method (if ... else "no results found")

Here is the code of a "simple search form" (thanks to jordinl) which I try to improve. I would like to add the case if there is no match found.

So, there is the view (views/users/index.html.erb)

<% form_tag users_path, :method => 'get' do %>
  <%= text_field_tag :search, params[:search] %>
  <%= submit_tag "Search", :name => nil %>
<% end %>

<% @users.each do |user| %>  
  <p><%= link_to "#{user.name}", user %></p>
.
.
.
<% end %>

The controller ( users_controller.rb)

def index
  @users = User.search(params[:search])
end

and the method in user model:

def self.search(search)
  search.blank? ? [] : all(:conditions => ['name LIKE ?', "%#{search.strip}%"])
end

I tried the following:

def self.search(search)
  if search.to_s.size < 1
    []
  else
    if  @users.size > 0
      all(:condi开发者_Go百科tions => ['name LIKE ?', "%#{search.strip}%"])
    else
      render :text => "No result found"
    end
  end
end

reporting the following error: "You have a nil object when you didn't expect it!..." (no instance in the array). Then, I tried to add

<% if @users? %>
  <% @users.each do |user| %>
.
.
.

In the view. But it doesn't work either.

I would be pleased to understand why I'm wrong on this. Thank you!

You're on the right track. Try this:

<% if (@users) %>
  <% if (@users.empty?) %>
    <p>No users found.</p>
  <% else %>
    <% @users.each do |user| %>  
      <p><%= link_to "#{user.name}", user %></p>
    <% end %>
  <% end %>
<% else %>
   <p>Use the search form to search for stuff.</p>
<% end %>

Change your search method to only return something if searching was used:

def self.search(search)
  search.present? and all(:conditions => [ 'name LIKE ?', "%#{search.strip}%" ])
end

you can't render in your model.

In your view:

<% form_tag users_path, :method => 'get' do %>
  <%= text_field_tag :search, params[:search] %>
  <%= submit_tag "Search", :name => nil %>
<% end %>

<% if @users.empty? %>
  No records found!
<% else %>
  <% @users.each do |user| %>  
    <p><%= link_to "#{user.name}", user %></p>
  <% end %>
<% end %>

In your model:

def self.search(search)
  search.blank? ? [] : all(:conditions => ['name LIKE ?', "%#{search.strip}%"])
end

You are close with your check on @users? but it should be:

<% if !@users.empty? %>
  <% @users.each do |user| %>
    ...
  <% end %>
<% else %>
  No users found.
<% end %>

This will work with your original self.search implementation which, correctly, is used just to find users and does not need to worry about reporting if none are found.

Your self.search method should return an array, either full or empty. Try:

in you model

def self.search
  self.all(:conditions => ['name LIKE ?', "%#{search.strip}%"])
end

and in your view

  <% if @users? %>
    <% @users.each do |user| %>
      …
    <% end %>
  <% else %>
    No result
  <% end %>