如何在未选中时使check_box_tag发布'false'或'0'参数？

Question

使用以下check_box_tag:

<%= check_box_tag 'object[boolean_attribute]', 1, object.boolean_attribute %>

我只能在一个方向更新boolean_attribute:从false到true.

如果默认情况下未选中(因为object.boolean_attribute为false)并且我检查它然后提交表单,则发布a:boolean_attribute => 1参数.

但是,当我尝试从true更新为false时,没有传递param,因此boolean_attribute保持为true.

换句话说,默认情况下检查时(因为object.boolean_attribute为true)并且我取消选中它然后提交表单,则不会发布:boolean_attribute => 0 .

如何取消选中此check_box_tag以发布:boolean_attribute => 0参数？

从api我无法弄清楚是否有一些选项可以轻松实现它:http: //api.rubyonrails.org/classes/ActionView/Helpers/FormTagHelper.html#method-i-check_box_tag

谢谢.

编辑

出于某种原因,我无法理解,在我的实际代码中(使用嵌套的多对多关联),hidden_​​field_tag无效.

<%= hidden_field_tag 'order[preparations_attributes][][cooked]', nil %>
<%= check_box_tag 'order[preparations_attributes][][cooked]', '1', preparation.cooked? %>

现在我遇到了相反的问题:我可以取消选中复选框,并按照预期更新准备工作,但是如果我选中复选框,它会使参数更加混乱.

以下是未选中框的已发布参数:

Parameters: {"utf8"=>"?", "authenticity_token"=>"bGgPGbk+Cuk2q+LEgqetmk4e7xie8dB3iMP9Cj3SUm0=", "order"=>{"customer_name"=>"Duccio Armenise", "duedate"=>"2012-04-25 09:24:00.000000", "preparations_attributes"=>[{"quantity"=>"1", "description"=>"custom recipe", "kind"=>"custom", "cooked"=>"", "recipe_id"=>"9", "id"=>"86", "quantities_attributes"=>[{"ingredient_id"=>"", "qty"=>"", "_destroy"=>"0"}, {"ingredient_id"=>"11", "qty"=>"5.0", "id"=>"193", "_destroy"=>"0"}], "_destroy"=>"0"}], "add_preparation"=>{"recipe_id"=>""}}, "continue"=>"Confirm", "id"=>"31"}

现在看看当我检查复选框时出现了一些混乱,从"cooked"=>""开始,出于某种原因,Rails太早关闭了prepare_attributes哈希!

Parameters: {"utf8"=>"?", "authenticity_token"=>"bGgPGbk+Cuk2q+LEgqetmk4e7xie8dB3iMP9Cj3SUm0=", "order"=>{"customer_name"=>"Duccio Armenise", "duedate"=>"2012-04-25 09:24:00.000000", "preparations_attributes"=>[{"quantity"=>"1", "description"=>"custom recipe", "kind"=>"custom", "cooked"=>""}, {"cooked"=>"1", "recipe_id"=>"9", "id"=>"86", "quantities_attributes"=>[{"ingredient_id"=>"", "qty"=>"", "_destroy"=>"0"}, {"ingredient_id"=>"11", "qty"=>"5.0", "id"=>"193", "_destroy"=>"0"}], "_destroy"=>"0"}], "add_preparation"=>{"recipe_id"=>""}}, "continue"=>"Confirm", "id"=>"31"}

编辑#2:

我想我遇到了与深层嵌套资源表单和param传递相关的Rails错误:https://github.com/rails/rails/issues/5937

现在我使用了select_tag:

<%= select_tag 'order[preparations_attributes][][cooked]', options_for_select({yes: 1, no: 0}, preparation.cooked? ? 1 : 0) %> 

我认为切换到select_tag以避免"hidden_​​field gotcha"是一种可接受的解决方法.

无论如何,谢谢你的答案!

Answer 1

check_box(没有_tag)帮助者添加隐藏字段来解决您的问题:

<%= check_box 'object', 'boolean_attribute', {}, 'true', 'false' %>

# result:
<input name="object[boolean_attribute]" type="hidden" value="false" />
<input id="object_boolean_attribute" name="object[boolean_attribute]" type="checkbox" value="true" />

UPD:处理嵌套资源(产品accepts_nested_attributes_for:line_items)

= form_for @product, url: '' do |f|
  %p
    = f.label :title
    = f.text_field :title

  = f.fields_for :line_items do |li|
    = li.check_box :approved
    = li.label :approved, li.object.id
    %br
  = f.submit

检查3个复选框中的2个给我params如下:

{...,"product"=> {"title"=>"RoR book","line_items_attributes"=> {"0"=> {"approved"=>"0","id"=>"47" },"1"=> {"approved"=>"1","id"=>"48"},"2"=> {"approved"=>"1","id"=>"51" },}"commit"=>"更新产品","操作"=>"action1","controller"=>"test"}

params 作为YAML的可读性:

product:
  title: RoR book
  line_items_attributes:
    '0':
      approved: '0'
      id: '47'
    '1':
      approved: '1'
      id: '48'
    '2':
      approved: '1'
      id: '51'

看到？没有隐藏字段,但检查/未检查状态清楚地区分.

有了这个params允许我使用一行代码来更新相关的line_items:

@product.update_attributes params[:product]

我希望它有所帮助.

Answer 2

您可以使用复选框上方的隐藏字段:

<%= hidden_field_tag 'object[boolean_attribute]', nil %>

这样,即使未选中您的复选框,您仍会收到nil提交.这对你有用吗？

Answer 3

如果有人有列类型布尔值并使用check_box_tag然后看看这个.它对我有用. <%= hidden_field_tag 'order[preparations_attributes][][cooked]', 'false' %> <%= check_box_tag 'order[preparations_attributes][][cooked]', true, preparation.cooked? %>