#29 group_by Month

May 09, 2007 | 5 minutes | Views, Active Support

Learn how to use the very useful group_by method to group an array by anything you want! In this episode I group an array of tasks by month then sort it properly.

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          tasks_controller.rb
                
        def index
  @tasks = Task.find(:all, :order => 'due_at, id', :limit => 50)
  @task_months = @tasks.group_by { |t| t.due_at.beginning_of_month }
end
        
def index
  @tasks = Task.find(:all, :order => 'due_at, id', :limit => 50)
  @task_months = @tasks.group_by { |t| t.due_at.beginning_of_month }
end

          tasks/index.rhtml
                
        <% @task_months.sort.each do |month, tasks| %>
  <h2><%= month.strftime('%B') %></h2>
  <% for task in tasks %>
    <div class="task">
      <strong><%= task.name %></strong>
      due on <%= task.due_at.to_date.to_s(:long) %>
    </div>
  <% end %>
<% end %>
        
        
        
        
        
        
        
        
        
      
<% @task_months.sort.each do |month, tasks| %>
  <h2><%= month.strftime('%B') %></h2>
  <% for task in tasks %>
    <div class="task">
      <strong><%= task.name %></strong>
      due on <%= task.due_at.to_date.to_s(:long) %>
    </div>
  <% end %>
<% end %>