Question

question has_many kpi到kpiquestions：

class Question < ActiveRecord::Base
  has_many :kpiquestions, dependent: :destroy
  has_many :kpis, through: :kpiquestions
end

class Kpi < ActiveRecord::Base
  has_many :kpiquestions, dependent: :destroy
  has_many :questions, through: :kpiquestions
end

class Kpiquestion < ActiveRecord::Base
  belongs_to :kpi
  belongs_to :question
end

现在我有一个有效的question表单，我可以使用复选框添加KPI：

= form_for @question do |f|
  = render "layouts/form_messages", target: @question
  .form-group
    = f.label "Name"
    = f.text_field :name
  .form-group
    = f.label "KPI's"
    %ul
      = hidden_field_tag "question[kpi_ids][]", nil
       - @kpis.each do |kpi|
        %li.checkbox
          = check_box_tag "question[kpi_ids][]", kpi.id, @question.kpi_ids.include?(kpi.id), "data-category" => kpi.id
          = kpi.name
  .form-group
      = f.submit(class: 'btn btn-default', value: "Save")

但是联接表kpiquestion有一个额外的属性weight。此属性也应添加到表单中，并带有text_field_tag。像这样：

= text_field_tag "question[kpi_ids][:weight]", kpi.weight, @question.kpi_ids.include?(kpi.id), "data-category" => kpi.weight

显然这不起作用，因为它现在返回一个错误，指出kpi没有名为weight的属性。那么如何将此属性添加到表单中呢？

Answer 1

一种方法是将整个form_for变成一个form_tag，传递给相关控制器中的post请求，然后唯一限制你可以传递的参数就是你选择允许控制器的参数-侧。显然这违反惯例，但对于这样的情况，它很有用。

以下是代码将更改为：

= form_tag question_index_path, :method => :post do
 = render "layouts/form_messages", target: @question *
 .form-group
   = label_tag "Name"
   = text_field_tag :name

 .form-group
   =label_tag :weight
   =text_field_tag :weight

 .form-group
   =label_tag "KPI's"
   = hidden_field_tag "question[kpi_ids][]", nil
   - @kpis.each do |kpi|
    %li.checkbox
      = check_box_tag "question[kpi_ids][]", kpi.id, @question.kpi_ids.include?(kpi.id), "data-category" => kpi.id
      = kpi.name

 .form-group
   =submit_tag("Save", class: btn btn-default)

has_many的形式：通过与连接表中的附加属性的关系

1 个答案: