是否可以为简单的类创建表单
我只想拥有编辑类属性的能力，而不是ActiveRecord类的inheritance者。
这是我的类/app/model/entry.rb：
class Entry attr_accessor :title, :body end 这是一个控制器：
class DiaryController < ApplicationController def new @entry = Entry.new end end
这是一个观点：
我在打开表单时收到错误消息：
条目的未定义方法`model_name’：Class
这是完整的堆栈：
Extracted source (around line #1): 1: 2:
3:
4: Full trace: activemodel (3.0.6) lib/active_model/naming.rb:95:in `model_name_from_record_or_class' activemodel (3.0.6) lib/active_model/naming.rb:82:in `singular' actionpack (3.0.6) lib/action_view/helpers/form_helper.rb:312:in `form_for' app/views/diary/new.html.erb:1:in `_app_views_diary_new_html_erb___902027577_26033568_187052521' actionpack (3.0.6) lib/action_view/template.rb:135:in `block in render' activesupport (3.0.6) lib/active_support/notifications.rb:54:in `instrument' actionpack (3.0.6) lib/action_view/template.rb:127:in `render' actionpack (3.0.6) lib/action_view/render/rendering.rb:59:in `block in _render_template' activesupport (3.0.6) lib/active_support/notifications.rb:52:in `block in instrument' activesupport (3.0.6) lib/active_support/notifications/instrumenter.rb:21:in `instrument' activesupport (3.0.6) lib/active_support/notifications.rb:52:in `instrument' actionpack (3.0.6) lib/action_view/render/rendering.rb:56:in `_render_template' actionpack (3.0.6) lib/action_view/render/rendering.rb:26:in `render' actionpack (3.0.6) lib/abstract_controller/rendering.rb:115:in `_render_template' actionpack (3.0.6) lib/abstract_controller/rendering.rb:109:in `render_to_body' actionpack (3.0.6) lib/action_controller/metal/renderers.rb:47:in `render_to_body' actionpack (3.0.6) lib/action_controller/metal/compatibility.rb:55:in `render_to_body' actionpack (3.0.6) lib/abstract_controller/rendering.rb:102:in `render_to_string' actionpack (3.0.6) lib/abstract_controller/rendering.rb:93:in `render' actionpack (3.0.6) lib/action_controller/metal/rendering.rb:17:in `render' actionpack (3.0.6) lib/action_controller/metal/instrumentation.rb:40:in `block (2 levels) in render' activesupport (3.0.6) lib/active_support/core_ext/benchmark.rb:5:in `block in ms' c:/Ruby192/lib/ruby/1.9.1/benchmark.rb:309:in `realtime' activesupport (3.0.6) lib/active_support/core_ext/benchmark.rb:5:in `ms' actionpack (3.0.6) lib/action_controller/metal/instrumentation.rb:40:in `block in render' actionpack (3.0.6) lib/action_controller/metal/instrumentation.rb:78:in `cleanup_view_runtime' activerecord (3.0.6) lib/active_record/railties/controller_runtime.rb:15:in `cleanup_view_runtime' actionpack (3.0.6) lib/action_controller/metal/instrumentation.rb:39:in `render' actionpack (3.0.6) lib/action_controller/metal/implicit_render.rb:10:in `default_render' actionpack (3.0.6) lib/action_controller/metal/implicit_render.rb:5:in `send_action' actionpack (3.0.6) lib/abstract_controller/base.rb:150:in `process_action' actionpack (3.0.6) lib/action_controller/metal/rendering.rb:11:in `process_action' actionpack (3.0.6) lib/abstract_controller/callbacks.rb:18:in `block in process_action' activesupport (3.0.6) lib/active_support/callbacks.rb:436:in `_run__776311234__process_action__123531476__callbacks' activesupport (3.0.6) lib/active_support/callbacks.rb:410:in `_run_process_action_callbacks' activesupport (3.0.6) lib/active_support/callbacks.rb:94:in `run_callbacks' actionpack (3.0.6) lib/abstract_controller/callbacks.rb:17:in `process_action' actionpack (3.0.6) lib/action_controller/metal/instrumentation.rb:30:in `block in process_action' activesupport (3.0.6) lib/active_support/notifications.rb:52:in `block in instrument' activesupport (3.0.6) lib/active_support/notifications/instrumenter.rb:21:in `instrument' activesupport (3.0.6) lib/active_support/notifications.rb:52:in `instrument' actionpack (3.0.6) lib/action_controller/metal/instrumentation.rb:29:in `process_action' actionpack (3.0.6) lib/action_controller/metal/rescue.rb:17:in `process_action' actionpack (3.0.6) lib/abstract_controller/base.rb:119:in `process' actionpack (3.0.6) lib/abstract_controller/rendering.rb:41:in `process' actionpack (3.0.6) lib/action_controller/metal.rb:138:in `dispatch' actionpack (3.0.6) lib/action_controller/metal/rack_delegation.rb:14:in `dispatch' actionpack (3.0.6) lib/action_controller/metal.rb:178:in `block in action' actionpack (3.0.6) lib/action_dispatch/routing/route_set.rb:62:in `call' actionpack (3.0.6) lib/action_dispatch/routing/route_set.rb:62:in `dispatch' actionpack (3.0.6) lib/action_dispatch/routing/route_set.rb:27:in `call' rack-mount (0.6.14) lib/rack/mount/route_set.rb:148:in `block in call' rack-mount (0.6.14) lib/rack/mount/code_generation.rb:93:in `block in recognize' rack-mount (0.6.14) lib/rack/mount/code_generation.rb:68:in `optimized_each' rack-mount (0.6.14) lib/rack/mount/code_generation.rb:92:in `recognize' rack-mount (0.6.14) lib/rack/mount/route_set.rb:139:in `call' actionpack (3.0.6) lib/action_dispatch/routing/route_set.rb:493:in `call' actionpack (3.0.6) lib/action_dispatch/middleware/best_standards_support.rb:17:in `call' actionpack (3.0.6) lib/action_dispatch/middleware/head.rb:14:in `call' rack (1.2.2) lib/rack/methodoverride.rb:24:in `call' actionpack (3.0.6) lib/action_dispatch/middleware/params_parser.rb:21:in `call' actionpack (3.0.6) lib/action_dispatch/middleware/flash.rb:182:in `call' actionpack (3.0.6) lib/action_dispatch/middleware/session/abstract_store.rb:149:in `call' actionpack (3.0.6) lib/action_dispatch/middleware/cookies.rb:302:in `call' activerecord (3.0.6) lib/active_record/query_cache.rb:32:in `block in call' activerecord (3.0.6) lib/active_record/connection_adapters/abstract/query_cache.rb:28:in `cache' activerecord (3.0.6) lib/active_record/query_cache.rb:12:in `cache' activerecord (3.0.6) lib/active_record/query_cache.rb:31:in `call' activerecord (3.0.6) lib/active_record/connection_adapters/abstract/connection_pool.rb:354:in `call' actionpack (3.0.6) lib/action_dispatch/middleware/callbacks.rb:46:in `block in call' activesupport (3.0.6) lib/active_support/callbacks.rb:416:in `_run_call_callbacks' actionpack (3.0.6) lib/action_dispatch/middleware/callbacks.rb:44:in `call' rack (1.2.2) lib/rack/sendfile.rb:107:in `call' actionpack (3.0.6) lib/action_dispatch/middleware/remote_ip.rb:48:in `call' actionpack (3.0.6) lib/action_dispatch/middleware/show_exceptions.rb:47:in `call' railties (3.0.6) lib/rails/rack/logger.rb:13:in `call' rack (1.2.2) lib/rack/runtime.rb:17:in `call' activesupport (3.0.6) lib/active_support/cache/strategy/local_cache.rb:72:in `call' rack (1.2.2) lib/rack/lock.rb:11:in `block in call' :10:in `synchronize' rack (1.2.2) lib/rack/lock.rb:11:in `call' actionpack (3.0.6) lib/action_dispatch/middleware/static.rb:30:in `call' railties (3.0.6) lib/rails/application.rb:168:in `call' railties (3.0.6) lib/rails/application.rb:77:in `method_missing' railties (3.0.6) lib/rails/rack/log_tailer.rb:14:in `call' rack (1.2.2) lib/rack/content_length.rb:13:in `call' rack (1.2.2) lib/rack/handler/webrick.rb:52:in `service' c:/Ruby192/lib/ruby/1.9.1/webrick/httpserver.rb:111:in `service' c:/Ruby192/lib/ruby/1.9.1/webrick/httpserver.rb:70:in `run' c:/Ruby192/lib/ruby/1.9.1/webrick/server.rb:183:in `block in start_thread'
是否可以使用form_for -tag编辑类属性？
jdc回答了这个问题，但未显示您请求的实际实现。 正如jdc所说，你需要包含一些ActiveModel模块，这将为你的ruby类提供你需要的function。
看起来你需要ActiveModel :: Naming和ActiveModel :: AttributeMethods。
class Entry extend ActiveModel::Naming include ActiveModel::AttributeMethods end
第一行将为您提供model_name ，第二行允许您的模型与表单助手一起使用。 您还可以使用其他行：查看在jdc的答案或Rails API中链接的博客。
更多链接详细信息：
这篇博客文章可以帮助您入门：
http://yehudakatz.com/2010/01/10/activemodel-make-any-ruby-object-feel-like-activerecord/
您可以包含一些ActiveRecord用于validation和序列化等模块的模块。 然后，如果你想要一个不会进入数据库的“保存”方法，只需创建一个。 我为联系模式做了那个。 它不是AR，只是一个普通的旧ruby对象，它引入了一些ActiveModel内容进行validation，提供了一些必需的方法，然后save方法只是触发一封电子邮件。 我认为甚至还有一个mixin可以用来处理初始化的东西，我正在做的是允许在创建时进行质量分配，但我没有密切关注它。 此对象看起来像前端的AR对象，因此基本帮助程序都可以工作。
class Contact include ActiveModel::Validations attr_accessor :id, :name, :email, :subject, :body validates :name, :presence => true validates :email, :presence => true validates :subject, :presence => true validates :body, :presence => true def initialize(attributes = {}) attributes.each do |key, value| self.send("#{key}=", value) end @attributes = attributes end def read_attribute_for_validation(key) @attributes[key] end def to_key end def save if self.valid? ContactNotifier.website_contact(self).deliver return true end false end end
看起来你得到的错误来自form_helper.rb中的以下行：
object_name = options[:as] || ActiveModel::Naming.param_key(object)
如果你硬编码：as =>“Entry”，你会得到更远的距离。 或者您可以扩展该类以响应方法model_name。 以下是调用model_name的ActiveModel :: Naming中的代码：
def self.model_name_from_record_or_class(record_or_class) (record_or_class.is_a?(Class) ? record_or_class : convert_to_model(record_or_class).class).model_name end
我可以继续接听电话，但我建议您自己关注。 最终，您将找到一个调用，该调用返回表单生成器在form_for中使用的属性和值的哈希值。
只需查看rails源代码，查看代码引发错误的位置，并扩展您的类以响应正确的调用。 继续这样做，你的模型会很好。 您不需要成为活动记录模型就可以像活动记录模型一样查看，行走和发出声音。
我发现这个RailsCasts第193集对你正在尝试做的事情非常有帮助。
首先，您的条目模型文件应该像这样开始：
class Entry < ActiveRecord::Base