Question

I’m currently reading Beginning Rails 3. I’m coming from PHP and trying to learn Ruby and Rails. I’m looking at a _form partial and I have a few questions. Specifically about the line:

    <%= form_for(@article) do |f| %>

What is the purpose of having the @article object in there as well as what is the function of variable f?

thanks,
mike

Answer 1

form_for accepts a model so that it can do a few things for you under the covers:

• It will read any current values off of that model and populate them in the fields you specify
• It will generate the proper URL for that resource (assuming you’re following conventions, otherwise you still have to specify it)
• It can display any validation errors on the model if you’re displaying after a POST.

If you just want the tag helpers, there’s also form_tag and friends