Question

我有一个用于创建投票的form_for。民意调查有许多poll_options，也称为嵌套属性。

问题 - 如何验证poll_options的数量？只有一个选项进行投票是没有意义的。

这是我的模特：

class PollOption < ApplicationRecord
  belongs_to :poll
  has_many :poll_responses
  accepts_nested_attributes_for :poll_options,
    reject_if: proc { |attributes| attributes['value'].blank? },
    allow_destroy: true

  validates :poll_options, length: {
    minimum: 1, too_short: "must be at least 2.",
    maximum: 5, too_long: "can be 5 at most."
  }

以下是我的观点：

<%= f.fields_for :poll_options do |poll_option| %>
  <%= render 'poll_option_fields', f: poll_option %>
<% end %>

我得到的错误与视图中的渲染线有关：

exception reentered

我也尝试过这种验证，但它既不起作用，也没有产生错误：

  def validates(value)
    if value.count < 1
      errors.add(:base, "must have at least 2 choices.")
    end
  end

更新：这是我的请求参数：

{"utf8"=>"✓", "authenticity_token"=>"6h+wZ+RUAOIp8iXFX0V9t0MSxTGtFHpe7PZS3fJeF3JejaIbAm2jidLyg0qYII26NYX+F1BH6FHWNCFJ7nzymQ==", "poll"=>{"user_id"=>"2", "active"=>"true", "question"=>"Example - Which of these do you like best?", "poll_options_attributes"=>{"0"=>{"value"=>"a", "_destroy"=>"0"}, "1"=>{"value"=>"b", "_destroy"=>"0"}, "2"=>{"value"=>"c", "_destroy"=>"0"}, "3"=>{"value"=>"", "_destroy"=>"0"}}}, "commit"=>"Save Poll", "controller"=>"polls", "action"=>"create"}

Answer 1

您应该在投票模型中验证，您可以在Poll中添加自定义验证，如下所示：

def validates_amount_of_polls
  if poll_options.size < 2
     errors.add(:base, "must have at least 2 choices")
  end
end

Rails验证提交的嵌套字段的数量

1 个答案: