Ruby on Rails Interview Question:

What is difference between form_for and form_tag?

Submitted by: Administrator

form_for and form_tag both are used to submit the form in
ruby on rails.
but the way of handling objects related to model is
different.

form_for:

you should use form_for for a specific model i.e while
crating an new row in database. form_for will perform the
standard http post which is having fields related to active
record objects.

here is the example for using form_for in ruby on rails:

<% form_for :user, @user, :url => { :action => "update" }
do |f| %>

then in here you can use the f object to create input
field.

First name: <%= f.text_field :firstname %>
Last name : <%= f.text_field :lastname %>
Biography : <%= f.text_area :biography %>

<% end %>

form_tag:

form_tag just creates an form as an normal form. form_for
will perform the standard http post without any model
backed and has normal fields. this is used mainly when
specific things need to be submitted via form


here is the example for using form_tag in ruby on rails:

<% form_tag '/posts' do -%>
<%= text_field_tag "post", "firstname" %>
<% end -%>
Submitted by: Administrator