# Passing un-editable model attributes from a form **URL:** \ **Category:** Rails\ **Created:** [March 21, 2007, 8:25pm UTC](https://www.ruby-forum.com/t/passing-un-editable-model-attributes-from-a-form/89638 "2007-03-21T20:25:27Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![Nathaniel](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/n/ba8739/32.png) [@Nathaniel](https://www.ruby-forum.com/u/Nathaniel)\ **Post date:** [March 21, 2007, 8:25pm UTC](https://www.ruby-forum.com/t/passing-un-editable-model-attributes-from-a-form/89638/1 "2007-03-21T20:25:27Z")
Dear anyone, I’m trying to create a very simple “form\_for” form which, when submitted, will create, via a RESTFUL controller, a new model object…all exactly as per the scaffold\_resource-generated model/controller/view but with one difference: At the time the form is generated, I compute the appropriate value for 2 of this model’s 3 columns based on instance variables floating around at that time (they depend on the view the user is being presented with) The form presents the user with the remaining 1 attribute to fill in. Upon submission, how do I get my 2 predetermined values to the controller within the standard params[:model\_name] hash? I don’t want to set my 2 attributes within the controller, as I want the controller “create” action to remain more generic than that. I imagine this is trivial…if you know how! Many thanks, Nathaniel ---
**Author:** ![Nathaniel](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/n/ba8739/32.png) [@Nathaniel](https://www.ruby-forum.com/u/Nathaniel)\ **Post date:** [March 21, 2007, 8:50pm UTC](https://www.ruby-forum.com/t/passing-un-editable-model-attributes-from-a-form/89638/2 "2007-03-21T20:50:32Z")
Look them up when you are generating the html form (if they are in a DB) and pass them back as hidden fields in the form. On Mar 21, 2:25 pm, Nathaniel [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) ---
**Author:** ![Nathaniel](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/n/ba8739/32.png) [@Nathaniel](https://www.ruby-forum.com/u/Nathaniel)\ **Post date:** [March 21, 2007, 9:02pm UTC](https://www.ruby-forum.com/t/passing-un-editable-model-attributes-from-a-form/89638/3 "2007-03-21T21:02:18Z")
Andrew, Matthew, Thanks to both of you. “form.hidden\_field” is exactly what I was after—I was ignorant to its existence! 3 hours wasted this afternoon; fixed in 3 minutes with your help. Thanks again Nathaniel ---
**Author:** ![Nathaniel](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/n/ba8739/32.png) [@Nathaniel](https://www.ruby-forum.com/u/Nathaniel)\ **Post date:** [March 21, 2007, 8:53pm UTC](https://www.ruby-forum.com/t/passing-un-editable-model-attributes-from-a-form/89638/4 "2007-03-21T20:53:53Z")
Nathaniel wrote: > The form presents the user with the remaining 1 attribute to fill in. > > Upon submission, how do I get my 2 predetermined values to the > controller within the standard params[:model\_name] hash? I don’t want to > set my 2 attributes within the controller, as I want the controller > “create” action to remain more generic than that. You mean other than just using hidden fields like so: form.hidden\_field(:some\_predefined\_attr). You just have to fill in the value for :some\_predfined\_attr in the object before you run your form\_for on it. -matthew