Rails：url_to scope

Question

在下面的一段代碼中（當然在視圖中）我有<td><%= post.full_hsh %></td>正確顯示了字段post.full_hsh的值，但是url_for給出了一個錯誤：No route matches {:controller=>"posts", :action=>"edit", :id=>nil}。

爲什麼post.full_hsh連續修正並且nil在下面的行中？由於

<% @posts.each do |post| %> 
<tr> 
    <td><%= truncate post.body, :length => 100, :separator => ' ' %>...</td> 
    <td><%= post.created_at %></td> 
    <td><%= post.full_hsh %></td>  
    <td><%= url_for :controller => 'posts', :action => 'edit', :id => post.full_hsh %></td> 
</tr> 
<% end %> 

編輯：

我routes.rb文件：

get "admin/index" 

root :to => 'home#index' 

#access posts via /posts/ab123c or /p/ab123c 
resources :posts, :path => 'p', :except => [:new, :index, :delete] 
resources :posts, :except => [:new, :index, :delete] 

match '/p/:id/delete' => 'posts#delete', :as => 'posts_delete' 
match '/admin' => 'admin#index' 

Answer 1

post.full_hsh是post異議的屬性。你可能想:id => post代替

要生成基於對象本身的URL，在這種情況下post，而不是一個對象的屬性（post.full_hsh）