我正好遇到这个问题，一开始看了代码里的注释没搞懂，最后看了楼上发的文档才弄懂。

代码的注释是这样的：

# You can use a block as well if your link target is hard to fit into the name parameter. ERB example:
     #
     #   <%= link_to(@profile) do %>
     #     <strong><%= @profile.name %></strong> -- <span>Check it out!</span>
     #   <% end %>
     #   # => <a href="/profiles/1">
     #          <strong>David</strong> -- <span>Check it out!</span>
     #        </a>

看这个链接里的文档 我根据文档里的这个

link_to(url, html_options = {}) do
  # name
end

举个例子：

<%= link_to logout_path, method: :delete, class: 'dropdown-item' do %>
  <i class="fa fa-sign-out" aria-hidden="true"></i>
  Log out
<% end %>

最后生成

<a class="dropdown-item" rel="nofollow" data-method="delete" href="/logout">
  <i class="fa fa-sign-out" aria-hidden="true"></i>
  Log out
</a>