How to create a Rails form_for with dynamic form fields from a database table?

Question

Sorry if this has been asked and answered in full somewhere. Not sure if I'm searching with the correct Rails speak for this question.

I'd like to create a Rails form based on fields stored in the database. Here's what my models looks like so far.

class Field < ActiveRecord::Base
  belongs_to :form
end

class Form < ActiveRecord::Base
  has_many :fields
end

The field model is very simple as of now with type:string and required:boolean columns. Name being the name of the control I'd like to create (textbox, checkbox, radiobutton). Ideally I'd like to do something like this:

<%= form_for [something here] do |f| %>
  <% @fields.each do |field| %>
    <%= field.type %><br />
  <% end %>
<% end %>

I'm struggling with finding a way to replace the line <%= field.type %> with a tag that would correctly render the field.type.

Is this possible? Would I be better off using a payload column in the field model storing field types and values as json/xml?

Answer 1

Like @TuteC mentioned, you can use the .send method to dynamically invoke each field, if you are saving the type:

<%= form_for [something here] do |f| %>
  <% @fields.each do |field| %>
    <%= f.send(field.type.to_sym, field.name) %><br />
  <% end %>
<% end %>