Question

我从1.2版本开始就没有使用过rails，但有些东西已经改变了。我有一个问题，我试图保存一个空模型，以使用：validates_presence_of获取属性验证错误，而我得到错误'无法将HashWithIndifferentAccess转换为字符串'。我将尝试简化我的代码，尽可能简洁地解决问题...

我的模特：

class Project < ActiveRecord::Base

    validates_presence_of :title, :description
    validates_uniqueness_of :title

    has_one :address

    accepts_nested_attributes_for :address, :allow_destroy => true
end

儿童模特：

class Address < ActiveRecord::Base
    validates_presence_of :title, :street
    belongs_to :project
end

控制器：

class ProjectsController < ApplicationController
    def create
        @project = Project.new(params[:project])
        if @project.save
            flash[:notice] = @project.title + ' successfully created'
            redirect_to projects_path
        else
            render :action => 'new'
        end
    end
end

视图：

<%= error_messages_for 'project' %>
<% form_for @project do |f| %>
<table width="100%" cellpadding="3" cellspacing="0">
    <tr>
        <td class="adminlabel">
            <label for="Title">Title</label>
        </td>
        <td class="adminbody">
            <%= f.text_field :title %>
        </td>
    </tr>   
    .....
    <% f.fields_for :address do |address| %>
    ....

只要我填写所有必填字段，此代码就添加和更新就好了，如果我留下任何空白我得到上面提到的错误，而不是提醒用户最优雅的方式有问题;）

请求参数：
{ “提交”=＆gt; “中保存”，
“项目”=＆GT; { “标题”=＆gt; “中”，
“注释”=＆gt; “中”，
“描述”=＆gt; “中”，
“address_attributes”=＆GT; { “城市”=＆gt; “中”，
“拉链”=＆gt; “中”，
“标题”=＆gt; “中”，
“国家”=＆gt; “中”，
“套件”=＆gt; “中”，
“街道”=＆gt; “中”，
“状态”=＆gt; “中”}}，
“authenticity_token”=＆gt;“iNPQZrf / oBv22vaI0toTGhknwx0aAU3BSvnIh6qgYQ8 =”}

我一直在寻找好几天，我的智慧结束了，如果有人能为我揭开这一点，我会非常感激。

提前致谢！

布兰登

PS - 请求的堆栈跟踪：

.../app/controllers/projects_controller.rb:27:in `+'  
.../app/controllers/projects_controller.rb:27:in `create'  
../actionpack-2.3.4/lib/action_controller/base.rb:1331:in `send'  
../actionpack-2.3.4/lib/action_controller/base.rb:1331:in `perform_action_without_filters'  
../actionpack-2.3.4/lib/action_controller/filters.rb:617:in `call_filters'  
../actionpack-2.3.4/lib/action_controller/filters.rb:610:in `perform_action_without_benchmark'  
../actionpack-2.3.4/lib/action_controller/benchmarking.rb:68:in `perform_action_without_rescue'  
../activesupport-2.3.4/lib/active_support/core_ext/benchmark.rb:17:in `ms'  
../activesupport-2.3.4/lib/active_support/core_ext/benchmark.rb:10:in `realtime'  
../activesupport-2.3.4/lib/active_support/core_ext/benchmark.rb:17:in `ms'  
../actionpack-2.3.4/lib/action_controller/benchmarking.rb:68:in `perform_action_without_rescue'  
../actionpack-2.3.4/lib/action_controller/rescue.rb:160:in `perform_action_without_flash'  
../actionpack-2.3.4/lib/action_controller/flash.rb:146:in `perform_action'  
../actionpack-2.3.4/lib/action_controller/base.rb:532:in `send'  
../actionpack-2.3.4/lib/action_controller/base.rb:532:in `process_without_filters'  
../actionpack-2.3.4/lib/action_controller/filters.rb:606:in `process'  
../actionpack-2.3.4/lib/action_controller/base.rb:391:in `process'  
../actionpack-2.3.4/lib/action_controller/base.rb:386:in `call'  
../actionpack-2.3.4/lib/action_controller/routing/route_set.rb:437:in `call'  
../actionpack-2.3.4/lib/action_controller/dispatcher.rb:87:in `dispatch'  
../actionpack-2.3.4/lib/action_controller/dispatcher.rb:121:in `_call'  
../actionpack-2.3.4/lib/action_controller/dispatcher.rb:130:in `build_middleware_stack'   
../activerecord-2.3.4/lib/active_record/query_cache.rb:29:in `call'  
../activerecord-2.3.4/lib/active_record/query_cache.rb:29:in `call'  
../activerecord-2.3.4/lib/active_record/connection_adapters/abstract/query_cache.rb:34:in `cache'  
..activerecord-2.3.4/lib/active_record/query_cache.rb:9:in `cache'   
../activerecord-2.3.4/lib/active_record/query_cache.rb:28:in `call'  
../activerecord-2.3.4/lib/active_record/connection_adapters/abstract/connection_pool.rb:361:in `call'  
../rack-1.0.1/lib/rack/head.rb:9:in `call'  
../rack-1.0.1/lib/rack/methodoverride.rb:24:in `call'  
../actionpack-2.3.4/lib/action_controller/params_parser.rb:15:in `call'  
../actionpack-2.3.4/lib/action_controller/session/cookie_store.rb:93:in `call'  
../actionpack-2.3.4/lib/action_controller/failsafe.rb:26:in `call'  
../rack-1.0.1/lib/rack/lock.rb:11:in `call'  
../rack-1.0.1/lib/rack/lock.rb:11:in `synchronize'  
../rack-1.0.1/lib/rack/lock.rb:11:in `call'  
../actionpack-2.3.4/lib/action_controller/dispatcher.rb:114:in `call'  
../actionpack-2.3.4/lib/action_controller/reloader.rb:34:in `run'  
../actionpack-2.3.4/lib/action_controller/dispatcher.rb:108:in `call'  
../rails-2.3.4/lib/rails/rack/static.rb:31:in `call'  
../rack-1.0.1/lib/rack/urlmap.rb:46:in `call'  
../rack-1.0.1/lib/rack/urlmap.rb:40:in `each'  
../rack-1.0.1/lib/rack/urlmap.rb:40:in `call'  
../rails-2.3.4/lib/rails/rack/log_tailer.rb:17:in `call'  
../rack-1.0.1/lib/rack/content_length.rb:13:in `call'  
../rack-1.0.1/lib/rack/chunked.rb:15:in `call'  
../rack-1.0.1/lib/rack/handler/mongrel.rb:64:in `process'
..... etc.

有点冗长，对不起;）

Answer 1

尝试添加

@project.address.build

到您的控制器。您需要实例化地址对象。

Answer 2

痕迹不是谎言。您遇到了第27行的问题。您发布的代码没有37行，但基于跟踪我愿意打赌它就是这一行。因为没有其他人有'+'。如果有一个隐含的+它的调用者将被列在跟踪中。

 flash[:notice] = @project.title + ' successfully created'

根据您的验证，它达到了这一点，这很奇怪。 validates_presence_of应该在nil，false或“”属性上添加错误。在控制台中运行时，验证是否按预期失败？

这是您的代码的友好控制台版本，可用于追踪您的问题。您应该可以将其粘贴到控制台中，以帮助追踪您的问题。

params = {
  "project"=> {
    "title"=>"", "notes"=>"","description"=>"", 
    "address_attributes"=>{
      "city"=>"", "zip"=>"","title"=>"","country"=>"",
      "suite"=>"","street"=>"","state"=>""
    }
   }
flash = {}

@project = Project.new(params[:project])
if @project.save
  flash[:notice] = @project.title + ' successfully created'
  puts "Saved. Flash: #{flash[:notice]}"
else
  puts "validations failed:" 
  puts @project.errors.full_messages.map{|m| "\t#{m}"}.join("\n")
end

Rails错误与验证和多个模型，无法将HashWithIndifferentAccess转换为String

2 个答案: