My form_for example works correctly, but *WHY* does it work?

Rails
1

Hello,

I am still new to Rails and have been trying to understand forms and
form_for, but it seems there are a number of ways to do / specify
things that all work fine. For example, I created this simple example
that works exactly how it should:

http://pastie.caboo.se/75110

My questions are:

  • I see many people do <% form_for :category, @category … %>,
    whereas I did just <% form_for :category … %>. Someone said this
    would be so the @category instance variable would be available to
    prepopulate the form on validation, but my example successfully
    prepopulates the form just fine on validation without the addition of
    @category. Why?

  • Doing :object => f causes us to use the ‘form’ object when
    specifying methods like form.text_field. Where did ‘form’ come from? I
    noticed I can achieve the same thing doing :locals => { :f => f } and
    then using f.text_field in the helper.

Thanks for the help in understanding this.

2

Some Browsers (e.g. FF) Save form data when you go back&forth in
browser history. Taht may be it. Test it in IE and i my guess is that
it won’t work there :wink:

rob schrieb: