局部模板中的计数器

<%= render :partial => "book", :collection => @books %>

 

大家都知道，这会渲染_book.html.erb局部模板，并遍历@books。下面就来看看_book.html.erb中的内容：

 

<div>
  Number: <%= book_counter %><br/>
  Title: <%= h book.title %><br/>
  Author: <%= h book.author %><br/>
</div>

 

这将会输出以下内容：

 

<div>
  Number: 0<br/>
  Title: Promises in Death<br/>
  Author: J. D. Robb<br/>
</div>

<div>
  Number: 1<br/>
  Title: One Day at a Time<br/>
  Author: Danielle Steel<br/>
</div>

<div>
  Number: 2<br/>
  Title: First Family<br/>
  Author: David Baldacci<br/>
</div>