Question

我现在一直在努力争取数据为我的嵌套表单保存。我基本上希望能够存储用户取消项目的理由，以及在项目取消之前的项目的最后阶段。但我似乎无法让行动cancel，cancel_save和cancel_params很好地发挥作用！

控制器

before_action :correct_user, only: [:show, :edit, :update, :destroy, :cancel, :cancel_save]

...

def cancel
  @project.build_project_close_reason
end

def cancel_save
  @project.build_project_close_reason(cancel_params)
  @project.update(project_status_id: 10)
  redirect_to root_path, notice: 'Project has been successfully cancelled.'
end

private 

def correct_user
  @user = current_user
  @project = current_user.projects.find_by(id: params[:id])
  end
  redirect_to user_projects_path, notice: "You are not authorised to view this project" if @project.nil?
end

def cancel_params
  params.require(:project).permit(project_close_reason_attributes: [:comment]).merge(project_close_reason_attributes: [project_id: @project.id, last_status_id: @project.project_status_id ])
end

模型

class Project < ApplicationRecord
  belongs_to :user
  has_one :project_close_reason
  accepts_nested_attributes_for :project_close_reason #adding this seemed to make no difference?
end

class ProjectCloseReason < ApplicationRecord
  belongs_to :project
end

class User < ApplicationRecord
... # All standard devise stuff
  has_many :projects
end

视图中的嵌套表单

<%= form_for([@user, @project], url: {action: "cancel_save"}, method: :post) do |f| %>

<%= fields_for :project_close_reason do |pcr| %>

  <div class="field entry_box">
    <%= pcr.label "Why are you cancelling this project? (This helps us improve!)" %>
    <%= pcr.text_area :comment, class: "form-control entry_field_text" %>
  </div>


<% end %>

  <div class="actions center space_big">
    <%= f.submit "Cancel Project", class: "btn btn-lg btn-warning" %>
  </div>

<% end %>

路线

devise_for :users
devise_for :admins

resources :users do
  resources :projects do
    get "cancel", :on => :member
    post "cancel" => 'projects#cancel_save', :on => :member
  end
end

这是我在尝试提交表单时遇到的错误：

ActionController::ParameterMissing in ProjectsController#cancel_save param is missing or the value is empty: project。它引用了cancel_params操作

感谢您的帮助！

更新

这是我拨打cancel_save

时的日志

Started POST "/users/2/projects/10/cancel" for ::1 at 2016-09-29 10:03:44 +0200
Processing by ProjectsController#cancel_save as HTML
Parameters: {"utf8"=>"✓", "authenticity_token"=>"h6K+VFyjW/dV189YOePWZm+Pmjey50xAMQIJb+c3dzpEaMv8Ckh3jQGOWfVdlfVH/FxolbB45fXvTO0cdplhkg==", "project_close_reason"=>{"comment"=>"b"}, "commit"=>"Cancel Project", "user_id"=>"2", "id"=>"10"}
User Load (11.2ms)  SELECT  "users".* FROM "users" WHERE "users"."id" = $1 ORDER BY "users"."id" ASC LIMIT $2  [["id", 2], ["LIMIT", 1]]
Project Load (0.7ms)  SELECT  "projects".* FROM "projects" WHERE "projects"."user_id" = $1 AND "projects"."id" = $2 LIMIT $3  [["user_id", 2], ["id", 10], ["LIMIT", 1]]
ProjectCloseReason Load (0.2ms)  SELECT  "project_close_reasons".* FROM "project_close_reasons" WHERE "project_close_reasons"."project_id" = $1 LIMIT $2  [["project_id", 10], ["LIMIT", 1]]
Completed 400 Bad Request in 22ms (ActiveRecord: 12.1ms)


ActionController::ParameterMissing (param is missing or the value is empty: project):

Answer 1

该错误表示没有名称为project的参数，您在params.require(:project)的{{1}}行中尝试使用该参数。我认为这是因为cancel params你提到form_for，这意味着[@user, @project]。所以user's project。致电project params must be inside user's时，请检查您的日志。必须有类似cancel_save的内容。

Answer 2

最后，我完成了它而不需要任何项目。这是我cancel_params中修订的projects_controller。对于其他任何想要进行这种添加剂数据库处理的人来说，如果你能这样做的话，我强烈建议你跳过嵌套形式的参数。 简单得多！

private

def cancel_params
  params.require(:project_close_reason).permit(:comment).merge(project_id: @project.id, last_status_id: @project.project_status_id )
end

嵌套表单的Rails参数

2 个答案: