Rails：发布后如何保存表单数据

Question

When I use form_for :model the data is saved when I submit the form.

However when I use form_tag , the data is lost after the form is processed.

I need to use form_tag because I have two models in one form.

Is there a way to save form data with form_tag ?

Answer 1

You are making two incorrect assumptions in your question. First, form_tag is not necessary or even recommended for multiple-model forms; Second, form_tag doesn't do anything fundamentally different from form_for , you are most likely not formatting the field names correctly for your controller.

In order to create a form with nested models, you need to use the fields_for helper in conjunction with form_for . The relationship needs to be defined first in the model with accepts_nested_attributes_for . Since you have not given us any information about your models, I will give you a made-up example:

class Person < ActiveRecord::Base
  has_one :address
  accepts_nested_attributes_for :address
end

class Address < ActiveRecord::Base
  belongs_to :person
end

This tells ActiveRecord that the Person model can accept attributes for Address, and will pass along the attributes to the correct model to be created.

<% form_for :person do |p| %>
  <% p.fields_for :address do |a| %>
    use the a form builder to create
    fields for the address model here
  <% end %>
<% end %>

chaining the fields_for helper from the p form builder lets the helpers generate attributes in the correct format.

More information: Nested Model Forms

Answer 2

Pretty much the same way as before except you'll need to build the params. You can look at your log to see how params are being sent.

eg.

def create
  @silly_hat = SillyHat.new( :name => params[:name], :size => params[:size], :colour => params[:colour] )
  if @silly_hat.save
    ...