The general question:
Is it bad style if you create a form in rails without associating it with a model and creating the desired object manually out of the params hash?
The specific problem (for reference,i might be on the wrong track):
For a little Rails 3 project I have to build a special form. The model is A has_many Bs. The amount of Bs is determined by an attribute of A, lets call it n. A has to have n Bs.
If the user hasn’t entered enough Bs he gets a form where he sees the already submitted Bs and fields for the not yet entered ones. As i dont want to have empty Bs i thought of soley creating them if something was entered in those fields. That lead me to this question.
The beauty of Rails is that it does provide with lots of niceties if you do go down the path they “push” you towards, however it is also understood that not every situtation will fall under their conventions which is why they make it possible to do what you mentioned. I wouldn’t stress over it too much if you honestly believe you have to create a form without associating a model with it.
My suggestion is to first think “how can I do this the Rails way”, because yes, if you can do it, it is generally going to be easier. However I think it is no issue at all if you can’t do it this way. The developers of Rails recognize this, and gives you tons of helper functions and the flexibility to “go off the path” to make your developing easier.