嗨,我正面临这个错误,
对rails来说是全新的,所以无法弄清楚导致它的原因
对rails来说是全新的,所以无法弄清楚导致它的原因
我的newBook.html.erb
<html>
<head>
<title> new Book </title>
</head>
<body>
<h1><%= @hello_message %></h1>
<h1>Add new book</h1>
<%= form_tag :action => 'create' %>
<p>
<label for="book_title">Title</label>:
<%= text_field 'book','title' %>
</p>
<p>
<label for="book_price">Price</label>:
<%= text_field 'book','price' %>
</p>
<p>
<label for="book_subject">Subject</label>:
<%= collection_select(:book,:subject_id,@subjects,:id,:name) %>
</p>
<p>
<label for="book_description">Description</label>
<br/>
<%= text_area 'book','description' %>
</p>
<%= submit_tag "Create" %>
<%= end_form_tag %>
<%= link_to 'Back',{:action => 'list'} %>
</body>
</html>
我的书模型：book.rb
class Book < ActiveRecord::Base attr_accessible :title,:price,:description,:created_at belongs_to :subject validates_presence_of :title validates_numericality_of :price,:message=>"Error Message" end
我的主题模型：subject.rb
class Subject < ActiveRecord::Base attr_accessible :name has_many :book end
堆栈跟踪是：
actionpack (3.2.13) lib/action_view/helpers/form_options_helper.rb:364:in `options_from_collection_for_select' actionpack (3.2.13) lib/action_view/helpers/form_options_helper.rb:600:in `to_collection_select_tag' actionpack (3.2.13) lib/action_view/helpers/form_options_helper.rb:191:in `collection_select' app/views/home/newBook.html.erb:19:in `_app_views_home_new_ook_html_erb__299261930_24178164' actionpack (3.2.13) lib/action_view/template.rb:145:in `block in render' activesupport (3.2.13) lib/active_support/notifications.rb:125:in `instrument' actionpack (3.2.13) lib/action_view/template.rb:143:in `render' # -- snipped --