diff options
Diffstat (limited to 'actionpack/lib/action_view/helpers')
-rw-r--r-- | actionpack/lib/action_view/helpers/form_helper.rb | 68 |
1 files changed, 55 insertions, 13 deletions
diff --git a/actionpack/lib/action_view/helpers/form_helper.rb b/actionpack/lib/action_view/helpers/form_helper.rb index 192b365bee..c1b1261ada 100644 --- a/actionpack/lib/action_view/helpers/form_helper.rb +++ b/actionpack/lib/action_view/helpers/form_helper.rb @@ -11,21 +11,25 @@ module ActionView # Form helpers are designed to make working with resources much easier # compared to using vanilla HTML. # - # Model-based forms are created with +form_for+. That method yields a form + # Forms for models are created with +form_for+. That method yields a form # builder that knows the model the form is about. The form builder is thus # able to generate default values for input fields that correspond to model - # attributes, and also convenient element names, IDs, endpoints, etc. + # attributes, and also convenient names, IDs, endpoints, etc. # # Conventions in the generated field names allow controllers to receive form # data nicely structured in +params+ with no effort on your side. # - # For example, to create a new +Person+ resource you typically set up a new - # instance in <tt>PeopleController#new</tt> action, <tt>@person</tt>, and - # write the form in <tt>new.html.erb</tt> this way: + # For example, to create a new person you typically set up a new instance of + # +Person+ in the <tt>PeopleController#new</tt> action, <tt>@person</tt>, and + # pass it to +form_for+: # # <%= form_for @person do |f| %> - # <%= f.text_field :first_name %> - # <%= f.text_field :last_name %> + # <%= f.label :first_name %>: + # <%= f.text_field :first_name %><br /> + # + # <%= f.label :last_name %>: + # <%= f.text_field :last_name %><br /> + # # <%= f.submit %> # <% end %> # @@ -35,16 +39,54 @@ module ActionView # <div style="margin:0;padding:0;display:inline"> # <input name="authenticity_token" type="hidden" value="NrOp5bsjoLRuK8IW5+dQEYjKGUJDe7TQoZVvq95Wteg=" /> # </div> - # <input id="person_first_name" name="person[first_name]" size="30" type="text" /> - # <input id="person_last_name" name="person[last_name]" size="30" type="text" /> + # <label for="person_first_name">First name</label>: + # <input id="person_first_name" name="person[first_name]" size="30" type="text" /><br /> + # + # <label for="person_last_name">Last name</label>: + # <input id="person_last_name" name="person[last_name]" size="30" type="text" /><br /> + # # <input id="person_submit" name="commit" type="submit" value="Create Person" /> # </form> # - # Because of the names of the input fields, the controller gets a <tt>:person</tt> - # nested hash in +params+ with the corresponding first and last names. That hash - # is ready to be passed to <tt>Person.create</tt> like this: + # As you see, the HTML reflects knowledge about the resource in several spots, + # like the path the form should be submitted to, or the names of the input fields. + # + # In particular, thanks to the conventions followed in the generated field names, the + # controller gets a nested hash <tt>params[:person]</tt> with the person attributes + # set in the form. That hash is ready to be passed to <tt>Person.create</tt>: + # + # if @person = Person.create(params[:person]) + # # success + # else + # # error handling + # end + # + # Interestingly, the exact same view code in the previous example can be used to edit + # a person. If <tt>@person</tt> is an existing record with name "John Smith" and ID 256, + # the code above as is would yield instead: + # + # <form action="/people/256" class="edit_person" id="edit_person_1" method="post"> + # <div style="margin:0;padding:0;display:inline"> + # <input name="_method" type="hidden" value="put" /> + # <input name="authenticity_token" type="hidden" value="NrOp5bsjoLRuK8IW5+dQEYjKGUJDe7TQoZVvq95Wteg=" /> + # </div> + # <label for="person_first_name">First name</label>: + # <input id="person_first_name" name="person[first_name]" size="30" type="text" value="John" /><br /> + # + # <label for="person_last_name">Last name</label>: + # <input id="person_last_name" name="person[last_name]" size="30" type="text" value="Smith" /><br /> + # + # <input id="person_submit" name="commit" type="submit" value="Update Person" /> + # </form> + # + # Note that the endpoint, default values, and submit button label are tailored for <tt>@person</tt>. + # That works that way because the involved helpers know whether the resource is a new record or not, + # and generate HTML accordingly. + # + # The controller would receive the form data again in <tt>params[:person]</tt>, ready to be + # passed to <tt>Person#update_attributes</tt>: # - # if person = Person.create(params[:person]) + # if @person.update_attributes(params[:person]) # # success # else # # error handling |