在ruby on rails应用程序中使用jquery ajax呈现flash消息时出错

Here's the error I get:

我得到的错误是:

ActionView::Template::Error (You have a nil object when you didn't expect it!
You might have expected an instance of Array.

It's referring to this code in a view partial:

它指的是视图部分中的代码:

<% flash.each do |key, value| %>
  <div class="<%= key %>"><%= value %></div>
<% end %>

I set the flash message in my micropost controller:

我在微博控制器中设置了flash消息:

def create
@micropost  = current_user.microposts.build(params[:micropost])
respond_to do |format|
  if @micropost.save
    flash[:success] = "Micropost created!"
    format.html { redirect_to root_path, :notice => 'success' }
    format.js

Here's my js code in views/microposts/create.js.erb:

以下是我的js代码在views/microposts/ create.s.erb:

$('div.notice').append('<%= render 'shared/flash' %>');

And the partial gets rendered dynamically in my application layout:

在我的应用程序布局中，部分被动态渲染:

<body>
  <div class="container">
    <%= render 'layouts/header' %>
    <section class="round">
  <div id= "notice"></div>
      <%= yield %>
    </section>
  <%= render 'layouts/footer' %>
  <%= debug(params) if Rails.env.development? %>
  </div>
</body>

How do I fix this error? What am I doing wrong?

如何修正这个错误?我做错了什么?

1 个解决方案

#1

The problem lies in the naming of your partial file.

问题在于部分文件的命名。

Rails tries to be clever with partials and automagically exposes a local variable that shares the same name as the partial's file name. It does this because the most common use-case for partials to to bind an HTML fragment to an instance of something, ie:

Rails试图巧妙地使用部分，并自动公开与部分文件名共享相同名称的本地变量。它之所以这样做，是因为部分将HTML片段绑定到某个实例的最常见用例是:

# the following is treated as: render :partial => "frobs", :collection = @frobs
render @frobs

Then, within your _frob.html.erb partial, you have a variable named frob which references the current instance from @frobs

然后,在你的_frob.html。erb分部，您有一个名为frob的变量，它引用来自@frobs的当前实例

In your case, this is colliding with the flash method exposed by ActionView: a local variable will always trump a method name. Try re-naming your partial to something else (ie, flash_message), keeping the content the same and see if that works.

在您的示例中，这与ActionView公开的flash方法相冲突:局部变量总是胜过方法名。试着把你的部分重新命名为其他的东西(比如flash_message)，保持内容不变，看看这样是否有效。

#1