遍历数据，以数组形式存储在Ruby on Rails中

Question

This is a very beginner question, but I've searched and can't find anything. I'm attempting to loop through an object, then store the information in an array (or object?) so that I can spit out a string of the items.

<% @da = [] %>
<% @report.data_items.each do |di| %>
      <% if di.status == "Complete" %>
        <% @da += di.url_metric.da %> #not sure how to append to the end of the array
      <% end %>
<% end %>

Help? Should I use an array or object?

Answer 1

Seems that you're doing this in ERB template for some reason. Don't. Keep templates clear and simple. Do this kind of calculations in controller.

Here's a better version:

@da = @report.data_items.select {|di| di.status == 'Complete'}.
                         map{|di| di.url_metric.da }

Answer 2

@da = @report.data_items.collect{|di| di.url_metric.da if di.status == "Complete"}.compact

Answer 3

Here's shorted varian of what you're trying to accomplish:

@da = @report.data_items.select do |item|
  item.status == "Complete"
end.map { |item| item.url_metric.da }.join(", ")