Question

Not sure if I’m asking this question properly, but here’s what I’m trying to do:

1. Select an event from a dropdown list (I know how to do this)

2. Passing that event ID to another part of the code in the form.

For example:

<%= form_for(@event_location) do |f| %>
  <%= select("event_location", :event_id, events_names_ids_hash, { :include_blank => true }) %>

Then pass the selected event_id to another part of the same form

Amending Question

How do I capture the value of :event_id, PRIOR to submitting the form

Answer 1

See if you can use this. Exact code might now work you need to make small modification but this is the concept using java script.
<%= form_for(@event_location) do |f| %>
<%= select(“event_location”, :event_id, events_names_ids_hash, :onchange =>”javascriptFunction()”, { :include_blank => true }) %>

<script type="text/javascript">
  function requestUrl()
  {
   var e = document.getElementById("event_id");
  var selectedId = e.options[e.selectedIndex].value;
   computedValue= "your calculation in javascript"
   document.getElementById("textbox").innerHTML=computedValue;
   }
</script>