ruby - Why do we declare a @page = Page.new under new action, in Rails? -

this question rails 3.2 , bit more complicated title suggests.

say have pages controller, restful actions. web app can create pages, display, edit , delete existing ones, , list of existing pages.

under new action, have code like

@page = page.new

so, when user visits /pages/new, , fill form_for(@page) do..end stuff, input data saved @page? instance, if title , content page model attributes, @page.title , @page.content return error or display seeking for? or form_for directly save values onto params?

if later case, why declare @page in new action? there form_for infer rails create new page model object rather existing one?

hopefully, wasn't confusing. :p

you can have form class writing

form_for :post 

in rails convention make form with

form_for @post 

because can render same form partial new, create (on validation errors) edit, , update (on validation error) actions. that's why need initialize new "empty" object in new action - keep interface uniform.