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diff --git a/guides/source/form_helpers.md b/guides/source/form_helpers.md index 8ab44ea0bb..b8681d493a 100644 --- a/guides/source/form_helpers.md +++ b/guides/source/form_helpers.md @@ -1,7 +1,7 @@ Form Helpers ============ -Forms in web applications are an essential interface for user input. However, form markup can quickly become tedious to write and maintain because of form control naming and their numerous attributes. Rails deals away with these complexities by providing view helpers for generating form markup. However, since they have different use-cases, developers are required to know all the differences between similar helper methods before putting them to use. +Forms in web applications are an essential interface for user input. However, form markup can quickly become tedious to write and maintain because of form control naming and their numerous attributes. Rails does away with these complexities by providing view helpers for generating form markup. However, since they have different use-cases, developers are required to know all the differences between similar helper methods before putting them to use. After reading this guide, you will know: @@ -148,7 +148,9 @@ Output: As with `check_box_tag`, the second parameter to `radio_button_tag` is the value of the input. Because these two radio buttons share the same name (age) the user will only be able to select one, and `params[:age]` will contain either "child" or "adult". -NOTE: Always use labels for checkbox and radio buttons. They associate text with a specific option and make it easier for users to click the inputs by expanding the clickable region. +NOTE: Always use labels for checkbox and radio buttons. They associate text with a specific option and, +by expanding the clickable region, +make it easier for users to click the inputs. ### Other Helpers of Interest @@ -215,7 +217,7 @@ will produce output similar to <input id="person_name" name="person[name]" type="text" value="Henry"/> ``` -Upon form submission the value entered by the user will be stored in `params[:person][:name]`. The `params[:person]` hash is suitable for passing to `Person.new` or, if `@person` is an instance of Person, `@person.update_attributes`. While the name of an attribute is the most common second parameter to these helpers this is not compulsory. In the example above, as long as person objects have a `name` and a `name=` method Rails will be happy. +Upon form submission the value entered by the user will be stored in `params[:person][:name]`. The `params[:person]` hash is suitable for passing to `Person.new` or, if `@person` is an instance of Person, `@person.update`. While the name of an attribute is the most common second parameter to these helpers this is not compulsory. In the example above, as long as person objects have a `name` and a `name=` method Rails will be happy. WARNING: You must pass the name of an instance variable, i.e. `:person` or `"person"`, not an actual instance of your model object. @@ -236,7 +238,7 @@ end The corresponding view `app/views/articles/new.html.erb` using `form_for` looks like this: ```erb -<%= form_for @article, url: {action: "create"}, html => {class: "nifty_form"} do |f| %> +<%= form_for @article, url: {action: "create"}, html: {class: "nifty_form"} do |f| %> <%= f.text_field :title %> <%= f.text_area :body, size: "60x12" %> <%= f.submit "Create" %> @@ -426,7 +428,7 @@ WARNING: when `:inlude_blank` or `:prompt:` are not present, `:include_blank` is You can add arbitrary attributes to the options using hashes: ```html+erb -<%= options_for_select([['Lisbon', 1, 'data-size': '2.8 million'], ['Madrid', 2, 'data-size': '3.2 million']], 2) %> +<%= options_for_select([['Lisbon', 1, {'data-size' => '2.8 million'}], ['Madrid', 2, {'data-size' => '3.2 million'}]], 2) %> output: @@ -458,7 +460,7 @@ As with other helpers, if you were to use the `select` helper on a form builder <%= f.select(:city_id, ...) %> ``` -WARNING: If you are using `select` (or similar helpers such as `collection_select`, `select_tag`) to set a `belongs_to` association you must pass the name of the foreign key (in the example above `city_id`), not the name of association itself. If you specify `city` instead of `city_id` Active Record will raise an error along the lines of ` ActiveRecord::AssociationTypeMismatch: City(#17815740) expected, got String(#1138750) ` when you pass the `params` hash to `Person.new` or `update_attributes`. Another way of looking at this is that form helpers only edit attributes. You should also be aware of the potential security ramifications of allowing users to edit foreign keys directly. +WARNING: If you are using `select` (or similar helpers such as `collection_select`, `select_tag`) to set a `belongs_to` association you must pass the name of the foreign key (in the example above `city_id`), not the name of association itself. If you specify `city` instead of `city_id` Active Record will raise an error along the lines of ` ActiveRecord::AssociationTypeMismatch: City(#17815740) expected, got String(#1138750) ` when you pass the `params` hash to `Person.new` or `update`. Another way of looking at this is that form helpers only edit attributes. You should also be aware of the potential security ramifications of allowing users to edit foreign keys directly. ### Option Tags from a Collection of Arbitrary Objects @@ -495,7 +497,7 @@ To leverage time zone support in Rails, you have to ask your users what time zon There is also `time_zone_options_for_select` helper for a more manual (therefore more customizable) way of doing this. Read the API documentation to learn about the possible arguments for these two methods. -Rails _used_ to have a `country_select` helper for choosing countries, but this has been extracted to the [country_select plugin](https://github.com/chrislerum/country_select). When using this, be aware that the exclusion or inclusion of certain names from the list can be somewhat controversial (and was the reason this functionality was extracted from Rails). +Rails _used_ to have a `country_select` helper for choosing countries, but this has been extracted to the [country_select plugin](https://github.com/stefanpenner/country_select). When using this, be aware that the exclusion or inclusion of certain names from the list can be somewhat controversial (and was the reason this functionality was extracted from Rails). Using Date and Time Form Helpers -------------------------------- @@ -534,7 +536,7 @@ The `:prefix` option is the key used to retrieve the hash of date components fro ### Model Object Helpers `select_date` does not work well with forms that update or create Active Record objects as Active Record expects each element of the `params` hash to correspond to one attribute. -The model object helpers for dates and times submit parameters with special names, when Active Record sees parameters with such names it knows they must be combined with the other parameters and given to a constructor appropriate to the column type. For example: +The model object helpers for dates and times submit parameters with special names; when Active Record sees parameters with such names it knows they must be combined with the other parameters and given to a constructor appropriate to the column type. For example: ```erb <%= date_select :person, :birth_date %> @@ -554,7 +556,7 @@ which results in a `params` hash like {:person => {'birth_date(1i)' => '2008', 'birth_date(2i)' => '11', 'birth_date(3i)' => '22'}} ``` -When this is passed to `Person.new` (or `update_attributes`), Active Record spots that these parameters should all be used to construct the `birth_date` attribute and uses the suffixed information to determine in which order it should pass these parameters to functions such as `Date.civil`. +When this is passed to `Person.new` (or `update`), Active Record spots that these parameters should all be used to construct the `birth_date` attribute and uses the suffixed information to determine in which order it should pass these parameters to functions such as `Date.civil`. ### Common Options @@ -620,7 +622,7 @@ Unlike other forms making an asynchronous file upload form is not as simple as p Customizing Form Builders ------------------------- -As mentioned previously the object yielded by `form_for` and `fields_for` is an instance of FormBuilder (or a subclass thereof). Form builders encapsulate the notion of displaying form elements for a single object. While you can of course write helpers for your forms in the usual way you can also subclass FormBuilder and add the helpers there. For example +As mentioned previously the object yielded by `form_for` and `fields_for` is an instance of FormBuilder (or a subclass thereof). Form builders encapsulate the notion of displaying form elements for a single object. While you can of course write helpers for your forms in the usual way, you can also subclass FormBuilder and add the helpers there. For example ```erb <%= form_for @person do |f| %> @@ -805,7 +807,7 @@ Sometimes when you submit data to an external resource, like payment gateway, fi <% end %> ``` -The same technique is available for the `form_for` too: +The same technique is also available for `form_for`: ```erb <%= form_for @invoice, url: external_url, authenticity_token: 'external_token' do |f| %> |