def export_to_csv

      @project = Project.find(params[:id])
        respond_to do |format|
          format.csv do
          @csv_string = FasterCSV.generate(:col_sep => ";") do |csv|    # calling method from gem FasterCSV

            # header row for Project
           csv << ["id", "name", "description", "budget", "added_on", "current_status"]
            # data rows for Project
            csv << [@project.id, @project.name, @project.description,
                    @project.budget, @project.added_on, @project.current_status]
            csv << []         # empty line

            # header rows for task that belongs to Project
            csv << ["id", "priority", "project.id", "title", "description",
                    "assigned_user", "completed", "created_at", "updated_at"]
             @project.tasks.each do |task|

              # data rows for task Project
              csv << [task.id, task.priority, task.project.id, task.title, task.description,
                      task.assigned_user, task.completed, task.created_at, task.updated_at]

             end
             end
        end
  end