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diff --git a/guides/source/form_helpers.md b/guides/source/form_helpers.md index cb45e38614..853227e2a1 100644 --- a/guides/source/form_helpers.md +++ b/guides/source/form_helpers.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.** + Form Helpers ============ @@ -96,7 +98,15 @@ form_tag({controller: "people", action: "search"}, method: "get", class: "nifty_ ### Helpers for Generating Form Elements -Rails provides a series of helpers for generating form elements such as checkboxes, text fields, and radio buttons. These basic helpers, with names ending in "_tag" (such as `text_field_tag` and `check_box_tag`), generate just a single `<input>` element. The first parameter to these is always the name of the input. When the form is submitted, the name will be passed along with the form data, and will make its way to the `params` hash in the controller with the value entered by the user for that field. For example, if the form contains `<%= text_field_tag(:query) %>`, then you would be able to get the value of this field in the controller with `params[:query]`. +Rails provides a series of helpers for generating form elements such as +checkboxes, text fields, and radio buttons. These basic helpers, with names +ending in `_tag` (such as `text_field_tag` and `check_box_tag`), generate just a +single `<input>` element. The first parameter to these is always the name of the +input. When the form is submitted, the name will be passed along with the form +data, and will make its way to the `params` hash in the controller with the +value entered by the user for that field. For example, if the form contains `<%= +text_field_tag(:query) %>`, then you would be able to get the value of this +field in the controller with `params[:query]`. When naming inputs, Rails uses certain conventions that make it possible to submit parameters with non-scalar values such as arrays or hashes, which will also be accessible in `params`. You can read more about them in [chapter 7 of this guide](#understanding-parameter-naming-conventions). For details on the precise usage of these helpers, please refer to the [API documentation](http://api.rubyonrails.org/classes/ActionView/Helpers/FormTagHelper.html). @@ -231,7 +241,7 @@ Upon form submission the value entered by the user will be stored in `params[:pe WARNING: You must pass the name of an instance variable, i.e. `:person` or `"person"`, not an actual instance of your model object. -Rails provides helpers for displaying the validation errors associated with a model object. These are covered in detail by the [Active Record Validations](./active_record_validations.html#displaying-validation-errors-in-views) guide. +Rails provides helpers for displaying the validation errors associated with a model object. These are covered in detail by the [Active Record Validations](active_record_validations.html#displaying-validation-errors-in-views) guide. ### Binding a Form to an Object @@ -265,14 +275,14 @@ There are a few things to note here: The resulting HTML is: ```html -<form accept-charset="UTF-8" action="/articles/create" method="post" class="nifty_form"> +<form accept-charset="UTF-8" action="/articles" method="post" class="nifty_form"> <input id="article_title" name="article[title]" type="text" /> <textarea id="article_body" name="article[body]" cols="60" rows="12"></textarea> <input name="commit" type="submit" value="Create" /> </form> ``` -The name passed to `form_for` controls the key used in `params` to access the form's values. Here the name is `article` and so all the inputs have names of the form `article[attribute_name]`. Accordingly, in the `create` action `params[:article]` will be a hash with keys `:title` and `:body`. You can read more about the significance of input names in the parameter_names section. +The name passed to `form_for` controls the key used in `params` to access the form's values. Here the name is `article` and so all the inputs have names of the form `article[attribute_name]`. Accordingly, in the `create` action `params[:article]` will be a hash with keys `:title` and `:body`. You can read more about the significance of input names in the [parameter_names section](#understanding-parameter-naming-conventions). The helper methods called on the form builder are identical to the model object helpers except that it is not necessary to specify which object is being edited since this is already managed by the form builder. @@ -290,7 +300,7 @@ You can create a similar binding without actually creating `<form>` tags with th which produces the following output: ```html -<form accept-charset="UTF-8" action="/people/create" class="new_person" id="new_person" method="post"> +<form accept-charset="UTF-8" action="/people" class="new_person" id="new_person" method="post"> <input id="person_name" name="person[name]" type="text" /> <input id="contact_detail_phone_number" name="contact_detail[phone_number]" type="text" /> </form> @@ -677,7 +687,14 @@ class LabellingFormBuilder < ActionView::Helpers::FormBuilder end ``` -If you reuse this frequently you could define a `labeled_form_for` helper that automatically applies the `builder: LabellingFormBuilder` option. +If you reuse this frequently you could define a `labeled_form_for` helper that automatically applies the `builder: LabellingFormBuilder` option: + +```ruby +def labeled_form_for(record, options = {}, &block) + options.merge! builder: LabellingFormBuilder + form_for record, options, &block +end +``` The form builder used also determines what happens when you do @@ -712,7 +729,7 @@ The two basic structures are arrays and hashes. Hashes mirror the syntax used fo the `params` hash will contain -```erb +```ruby {'person' => {'name' => 'Henry'}} ``` |