Ruby on rails 表单提交后，如何访问控制器上嵌套属性的表单_？

我需要访问嵌套属性的字段\u，但我一直遇到以下错误：

nil:NilClass的未定义方法“[]”

对于行：

params[:braintree_subscription_attributes][0][:plan_token]
params["braintree_subscription_attributes"][0]["plan_token"]
braintree_account_params[:braintree_subscription_attributes][0][:plan_token]
braintree_account_params["braintree_subscription_attributes"][0]["plan_token"]

params[:braintree_subscription_attributes]['0'][:plan_token]
params["braintree_subscription_attributes"]['0']["plan_token"]
braintree_account_params[:braintree_subscription_attributes]['0'][:plan_token]
braintree_account_params["braintree_subscription_attributes"]['0']["plan_token"]

Parameters: {"utf8"=>"✓", "braintree_account"=>{"first_name"=>"asfd", "last_name"=>"asfd", "braintree_subscription_attributes"=>{"plan_token"=>"4zfr"}}, "user_id"=>"1"}

class BraintreeAccount < ApplicationRecord
  has_one :braintree_subscription
  accepts_nested_attributes_for :braintree_subscription
end

class BraintreeSubscription < ApplicationRecord
  belongs_to :braintree_account
end

braintree\u帐户\u参数[：braintree\u订阅\u属性][0][：计划\u令牌]

我试过：

params[:braintree_subscription_attributes][0][:plan_token]
params["braintree_subscription_attributes"][0]["plan_token"]
braintree_account_params[:braintree_subscription_attributes][0][:plan_token]
braintree_account_params["braintree_subscription_attributes"][0]["plan_token"]

params[:braintree_subscription_attributes]['0'][:plan_token]
params["braintree_subscription_attributes"]['0']["plan_token"]
braintree_account_params[:braintree_subscription_attributes]['0'][:plan_token]
braintree_account_params["braintree_subscription_attributes"]['0']["plan_token"]

Parameters: {"utf8"=>"✓", "braintree_account"=>{"first_name"=>"asfd", "last_name"=>"asfd", "braintree_subscription_attributes"=>{"plan_token"=>"4zfr"}}, "user_id"=>"1"}

class BraintreeAccount < ApplicationRecord
  has_one :braintree_subscription
  accepts_nested_attributes_for :braintree_subscription
end

class BraintreeSubscription < ApplicationRecord
  belongs_to :braintree_account
end

没有一个奏效

这：
params[：braintree\u帐户][：braintree\u订阅\u属性]。第一个[：计划\u令牌]

错误：
ActionController的未定义方法优先#

我的参数：

params[:braintree_subscription_attributes][0][:plan_token]
params["braintree_subscription_attributes"][0]["plan_token"]
braintree_account_params[:braintree_subscription_attributes][0][:plan_token]
braintree_account_params["braintree_subscription_attributes"][0]["plan_token"]

params[:braintree_subscription_attributes]['0'][:plan_token]
params["braintree_subscription_attributes"]['0']["plan_token"]
braintree_account_params[:braintree_subscription_attributes]['0'][:plan_token]
braintree_account_params["braintree_subscription_attributes"]['0']["plan_token"]

Parameters: {"utf8"=>"✓", "braintree_account"=>{"first_name"=>"asfd", "last_name"=>"asfd", "braintree_subscription_attributes"=>{"plan_token"=>"4zfr"}}, "user_id"=>"1"}

class BraintreeAccount < ApplicationRecord
  has_one :braintree_subscription
  accepts_nested_attributes_for :braintree_subscription
end

class BraintreeSubscription < ApplicationRecord
  belongs_to :braintree_account
end

强参数：

参数require（：braintree\u account）.permit（…，braintree\u subscription\u属性：[:id，：plan\u token]）

型号：

params[:braintree_subscription_attributes][0][:plan_token]
params["braintree_subscription_attributes"][0]["plan_token"]
braintree_account_params[:braintree_subscription_attributes][0][:plan_token]
braintree_account_params["braintree_subscription_attributes"][0]["plan_token"]

params[:braintree_subscription_attributes]['0'][:plan_token]
params["braintree_subscription_attributes"]['0']["plan_token"]
braintree_account_params[:braintree_subscription_attributes]['0'][:plan_token]
braintree_account_params["braintree_subscription_attributes"]['0']["plan_token"]

Parameters: {"utf8"=>"✓", "braintree_account"=>{"first_name"=>"asfd", "last_name"=>"asfd", "braintree_subscription_attributes"=>{"plan_token"=>"4zfr"}}, "user_id"=>"1"}

class BraintreeAccount < ApplicationRecord
  has_one :braintree_subscription
  accepts_nested_attributes_for :braintree_subscription
end

class BraintreeSubscription < ApplicationRecord
  belongs_to :braintree_account
end

class BraintreeAccount

如何访问计划令牌？
因为这是一个have-one，而不是have-many，所以属性中的嵌套对象不会超过1个。仅当预期有多个子项时，才需要使用数组语法

braintree_account_params[:braintree_subscription_attributes][:plan_token]

请提供完整的控制器代码，因为解决方案就在那里。您发布的
参数
就是您应该使用/调查的内容，以找到如何访问发布的
braintree\u订阅
。然后，更进一步：确保你的强参数没有阻塞所需的字段（但这似乎没问题）。也很容易根据发布的参数进行验证，imho这是正确的。