Ruby on rails 使注释（在rails指南示例中）可编辑

我正在按照rails 3指南学习rails

博客应用程序现在已经运行，但是我想让评论可以编辑，并在post show页面中更新、创建表单。因此，我做了以下修改：

post.show.htm.erb：

<h2>Comments</h2>
<% @post.comments.each do |comment| %>
  <tr>
    <td><%= comment.commenter %></td>
    <td><%= comment.body %></td>
    <td><%= link_to 'Edit', edit_post_comment_path(@post,comment) %></td>
    <td><%= link_to 'Destroy', post_comment_path(@post,comment), confirm: 'Are you sure?', method: :delete %></td>
  </tr>
<% end %>
</table>

<h2>Add a comment:</h2>

#here,I can not set the form_for property.
<%= form_for([@post,@comment],:url=>post_comment_path) do |f| %>
  <div class="field">
    <%= f.label :commenter %><br />
    <%= f.text_field :commenter %>
  </div>
  <div class="field">
    <%= f.label :body %><br />
    <%= f.text_area :body %>
  </div>
  <div class="actions">
    <%= f.submit %>
  </div>
<% end %>

我得到一个错误：

No route matches {:action=>"show", :controller=>"comments"}

事实上，正如你所看到的，我在CommentController中有表演动作

而且，我想知道为什么它会访问评论#show action

这是我的路线：

    post_comments GET    /posts/:post_id/comments(.:format)          comments#index
                  POST   /posts/:post_id/comments(.:format)          comments#create
 new_post_comment GET    /posts/:post_id/comments/new(.:format)      comments#new
edit_post_comment GET    /posts/:post_id/comments/:id/edit(.:format) comments#edit
     post_comment GET    /posts/:post_id/comments/:id(.:format)      comments#show
                  PUT    /posts/:post_id/comments/:id(.:format)      comments#update
                  DELETE /posts/:post_id/comments/:id(.:format)      comments#destroy
            posts GET    /posts(.:format)                            posts#index
                  POST   /posts(.:format)                            posts#create
         new_post GET    /posts/new(.:format)                        posts#new
        edit_post GET    /posts/:id/edit(.:format)                   posts#edit
             post GET    /posts/:id(.:format)                        posts#show
                  PUT    /posts/:id(.:format)                        posts#update
                  DELETE /posts/:id(.:format)                        posts#destroy
       home_index GET    /home/index(.:format)                       home#index
             root        /                                           home#index

---

/posts/:id

将触发

posts\show

。为什么

评论#显示
？
如果需要编辑文章，请添加

def edit
  @post = Post.find(params[:id])
end

def update
  @post = Post.find(params[:id])
  if @post.update_attributes(params[:post])
    redirect_to some_path and return
  end
  render 'edit' #error
end

编辑表单应向服务器发送PUT请求。rails使用routes文件将url和请求（如GET/POST/PUT/DELETE）映射到控制器操作

这里

请求被放置，控制器为PostsController，操作为update

而且

如果表单是POST/PUT/DELETE，则需要从表单中传递http请求。
你可以为“编辑”这样做

<%= form_for([@post,@comment],:url=>post_comment_path, :method => :put) do |f| %>

post|u comment_path，：method=>：put）do | f |%>

映射到PostsController的显示请求。默认情况下，格式为html。有关更多信息，请详细查看服务器日志

def edit
  @post = Post.find(params[:id])
end

def update
  @post = Post.find(params[:id])
  if @post.update_attributes(params[:post])
    redirect_to some_path and return
  end
  render 'edit' #error
end

PUT    /posts/:id(.:format)                        posts#update

post GET    /posts/:id(.:format)                        posts#show

<%= form_for([@post,@comment],:url=>post_comment_path, :method => :put) do |f| %>