How do I obtain a selected value in Ruby on Rails 2.3.8?

Question

My select_tag is as follows.

<%= select_tag "group", options_from_collection_for_select(@groups, "id", "gname") %>

How do I obtain the selected value in my controller?

Answer 1

Use square brackets.

select_tag "group[]", options_for ....

Note the []. Rails will then store this as {"group" => [one option for each form]}.

If it's important to know which select provided which value, you can nest them, so

select_tag "group[bob]", ... 

will provide {"group" => {"bob" => selected_option}}.

Basically, [] stores it in an array, and [key] stores it in a hash with that key.

Then in controller, you can use as:

params["group"] , which should be an array of the various selects on the page.

Answer 2

尝试puts params并检查控制台以查看发送到控制器的值。

Answer 3

那应该是控制器中的params[:group] 。