Question

The functionality I want to achieve with this is to have different fields based on the action the user is currently on.

The generic scaffold bundles the form into a partial and renders it in the new and edit actions. In a typical signup case, one may not want to update the password everytime the profile is updated. One way I used to solve this in the past is to create separate forms for new and edit; including the password in new only. Obviously, most fields repeat themselves. Is there a way to keep the partial but omit (thereby not updating) some fields on the form per action?

Answer 1

Let me assume you are building the form for user model.So in controller you will have

def new 
  @user = User.new 
  .....
end 

def edit
  @user = User.find(params[:id])
  ....
end 

In the form partial use

<% if @user.new_record? %>
 <%= f.field_type :field_name %>
<% end %>

This will not render the field during edit/update.