Question

我第一次使用Rails 3，并创建一个表单，其中每一行代表一个新的记录实例，一个动作按钮可以同时创建多个记录。我一直在关注 Rails 3 Edit Multiple Records in a Single Form 一般来说，一切似乎都运作良好。但是，仔细检查params []数组后，我注意到有些值是意外的。例如，如果复选框设置在窗体的某一行上，则在params []数组中，它位于窗体的错误行中。此外，params数组中似乎还有一个记录比实际应该创建的记录多一个。更具体地说


rails --version
Rails 3.0.0
ruby -v
ruby 1.9.2p0 (2010-08-18 revision 29036) [i686-linux]

database schema:
  create_table "observations", :force => true do |t|
    t.string   "name"
    t.boolean  "good"
    t.datetime "created_at"
    t.datetime "updated_at"
  end

视图： testapp /应用/视图/观测/ editlist.html.erb

<% form_tag :action => 'update_observations', :method => :put do %>  
 <table>
  <% for observation in @observations %>  
    <%= fields_for 'observations[]', observation do |f| %>  
       <tr>
  <td>
         <%= f.label :name %>
         <%= f.text_field :name %></td>
  <td>
         <%= f.label :good %>
         <%= f.check_box :good %> </td>
       </tr>
    <% end %>  
  <% end %>  
 </table>
  <p><%= submit_tag "Submit" %></p>  
 <% end %>

控制器

  def editlist
    @num = 2
    @observations = Array(@num)
    (0..@num-1).each do |index|
      @observations[index] = Observation.new
    end

    respond_to do |format|
      format.html 
      format.xml  { head :ok }
    end   
  end

  def update_observations
    @observations = params[:observations].collect { |observation|  Observation.new(observation) }
    @observations.each do |obs|
        obs.save
   end
   redirect_to :action => 'index'
   end

路线：

  match 'observations/update_observations'
  match 'observations/editlist'
  resources :observations

Gemfile
source 'http://rubygems.org'
gem 'rails', '3.0.0'
gem 'sqlite3-ruby', :require => 'sqlite3'

如果我然后创建两个新的观察，称为first（good = true）和second（good = false），这里是来自rails服务器输出的params值

Started POST "/observations/update_observations?method=put" for 127.0.0.1 at 2011-01-17 12:26:55 +1030
  Processing by ObservationsController#update_observations as HTML
  Parameters: {"utf8"=>"✓", "authenticity_token"=>"CnTHEE7L1tPndgmNZF2KEGddU/WlDf6jl8SAEiwCz6Q=", "observations"=>[{"name"=>"first", "good"=>"0"}, {"good"=>"1", "name"=>"second"}, {"good"=>"0"}], "commit"=>"Submit", "method"=>"put"}
  SQL (0.3ms)   SELECT name
 FROM sqlite_master
 WHERE type = 'table' AND NOT name = 'sqlite_sequence'

  SQL (0.4ms)  INSERT INTO "observations" ("created_at", "good", "name", "updated_at") VALUES ('2011-01-17 01:56:55.262688', 'f', 'first', '2011-01-17 01:56:55.262688')
  SQL (0.4ms)  INSERT INTO "observations" ("created_at", "good", "name", "updated_at") VALUES ('2011-01-17 01:56:55.347775', 't', 'second', '2011-01-17 01:56:55.347775')
  SQL (0.4ms)  INSERT INTO "observations" ("created_at", "good", "name", "updated_at") VALUES ('2011-01-17 01:56:55.458927', 'f', NULL, '2011-01-17 01:56:55.458927')
Redirected to http://localhost:3000/observations
Completed 302 Found in 264ms

从params []可以看出，虽然我选择第一条记录而不是第二条记录为true，但第一条记录为false，第二条记录为true。此外，还有第三条记录，其中good =＆gt;是的，即使我只要求两条记录（或者我认为是这样！）

我最初的问题是复杂的形式，所以这是我尝试在一个简单的例子中重建它。非常感谢，wa

注意：我刚刚用两个字符串字段重做了这个例子：即 schema.rb

  create_table "observations", :force => true do |t|
    t.string   "name"
    t.string   "good"
    t.datetime "created_at"
    t.datetime "updated_at"
  end

表单参数

没有问题

Started POST "/observations/update_observations?method=put" for 127.0.0.1 at 2011-01-17 13:21:24 +1030
  Processing by ObservationsController#update_observations as HTML
  Parameters: {"utf8"=>"✓", "authenticity_token"=>"CnTHEE7L1tPndgmNZF2KEGddU/WlDf6jl8SAEiwCz6Q=", "observations"=>[{"name"=>"six", "good"=>"6"}, {"name"=>"seven", "good"=>"7"}], "commit"=>"Submit", "method"=>"put"}
  SQL (0.3ms)   SELECT name
 FROM sqlite_master
 WHERE type = 'table' AND NOT name = 'sqlite_sequence'

  SQL (0.5ms)  INSERT INTO "observations" ("created_at", "good", "name", "updated_at") VALUES ('2011-01-17 02:51:24.248045', '6', 'six', '2011-01-17 02:51:24.248045')
  SQL (0.3ms)  INSERT INTO "observations" ("created_at", "good", "name", "updated_at") VALUES ('2011-01-17 02:51:24.318928', '7', 'seven', '2011-01-17 02:51:24.318928')
Redirected to http://localhost:3000/observations

所以也许这与复选框有关？

（顺便说一句，通常使用布尔字段并使用复选框没有问题，使用生成的脚手架可以正常工作。当我将多个记录的表单的html与复选框进行比较时，以及单个表单的形式使用复选框（来自脚手架生成器）记录它们看起来是相同的。）

在单个表单示例上编辑多个记录具有意外的参数值

0 个答案: