# Q: ActiveForm? **URL:** \ **Category:** Rails\ **Created:** [November 13, 2005, 3:56pm UTC](https://www.ruby-forum.com/t/q-activeform/94899 "2005-11-13T15:56:51Z")\ **Posts on this page:** 4\ **Page:** 1

**Author:** ![sross](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/bbce88/32.png) [@sross](https://www.ruby-forum.com/u/sross)\ **Post date:** [November 13, 2005, 3:56pm UTC](https://www.ruby-forum.com/t/q-activeform/94899/1 "2005-11-13T15:56:51Z")

This question pops in and out of the mailing list and I’m wondering whether others have solved it. Consider the case where the user is filling out a form but there is no underlying database record (say the contents of the form are emailed someplace then discarded). It would be great to use: \<%= text\_field(:my\_fine\_form, ‘last\_name’) %\> \<%= text\_field(:my\_fine\_form, ‘first\_name’) %\> # etc. Then have params[:my\_fine\_form] automagically populate some object just as it does the model. E.g., @my\_fine\_data = MyFineForm.find() # populates from params[:my\_fine\_form] redirect\_to :action =\> ‘entry\_form’ unless @my\_fine\_data.valid? And even cooler, a form model: def MyFineForm \< ActiveForm :validates\_presence\_of :last\_name :persists\_in\_session =\> true; # and blah, blah, blah end I’d write this myself – I may even have to – but I wanted to make sure nobody else already has. Thanks ---

Steve R. wrote: > :validates\_presence\_of :last\_name > :persists\_in\_session =\> true; > > # and blah, blah, blah > > end > > I’d write this myself – I may even have to – but I wanted to make sure > nobody else already has. Well, my hacky way of doing this was just to leverage the entire ActiveRecord class, but use a memory based sqlite table that represents the fields in the form I want. In the model class itself, I set up the table structure to represent the fields I want filled out. There’s nothing stored in a permanent database. One could even override save and create to throw exceptions in case anybody does try to save anything to the db. ActiveForm could derive from ActiveRecord::Base and use a memory backed sqlite database as a backend for ActiveRecord to inflect off of. Here’s the code: # There are no records that are stored in a database for the model, so # build a memory based Sqlite database to build a schema to help build # an ActiveRecord. # # Because no objects instances of this model are stored in the # database, conventional usage of an object of this model is to have # the object’s id be the same as the output type’s id so linking them # up is easy. class Post \< ActiveRecord::Base unless const\_defined? :SQLITE\_SETUP SQLITE\_SETUP = true self.establish\_connection(:adapter =\> ‘sqlite’, :database =\> ‘:memory:’) conn = self.connection conn.create\_table(self.table\_name, :primary\_key =\> self.primary\_key) do |t| t.column :count, :integer end end attr\_accessible :count validates\_presence\_of :count validates\_numericality\_of :count, :only\_integer =\> true end Regards, Blair ---

Great solution. Just a couple notes: 1. Not everyone has sqlite. Notably, most Win32 installs don’t. Fortunately, that’s not where I’m developing or where I’m targeting, to I’m ok. 2. self.establish\_connection(:adapter =\> ‘sqlite’, :database =\> ‘:memory:’) – should read – self.establish\_connection(:adapter =\> ‘sqlite’, :dbfile =\> ‘:memory:’) Steve ---

Steve R. wrote: > Great solution. Just a couple notes: > > 1. Not everyone has sqlite. Notably, most Win32 installs don’t. Fortunately, > that’s not where I’m developing or where I’m targeting, to I’m ok. That’s good! > 1. self.establish\_connection(:adapter =\> ‘sqlite’, :database =\> ‘:memory:’) > – should read – > self.establish\_connection(:adapter =\> ‘sqlite’, :dbfile =\> ‘:memory:’) Actually not. In a recent RoR release, this was changed: [http://dev.rubyonrails.com/changeset/2825](http://dev.rubyonrails.com/changeset/2825) Regards, Blair