1. 默认参数
Ruby代码
<%= render :partial => "account" %>
默认本地有个变量@account, 传递过去，render到的partial（_account.erb）有个变量account
2. 单独参数 locals
locals传递一组hash参数hash 值是本地的变量，hash的key是partial里的变量
Ruby代码
<%= render :partial => "account", :locals => { :account => @buyer } %>
<% for ad in @advertisements %>
<%= render :partial => "ad", :locals => { :ad => ad } %>
<% end %>
上面两个render分别
传递本地变量@buyer到_account.erb里叫account的参数
传递本地变量ad到_ad.erb里叫ad
3
根据1默认参数下面两个是一样的
Ruby代码
<%= render :partial => "contract", :locals => { :contract => @contract } %>
<%= render :partial => "contract" %>
4. as使用
用来改变传递之后，partial里变量的名称，如下，render方式是一样的。
Ruby代码
<%= render :partial => "contract", :as => :agreement
<%= render :partial => "contract", :locals => { :agreement => @contract }
传递@contract到_contract.erb里，partial里的变量名为agreement
5. object使用
object最简单，就是把一个变量原名传递到partial里，
所以什么都记不清楚的时候，就用object多写点都能表达
如下：
Ruby代码
<%= render :partial => "account", :object => @buyer %> <% for ad in @advertisements %> <%= render :partial => "ad", :object => ad %> <% end %>
传递@buyer到_account.erb的partial里变量名还是@buyer
传递ad到_ad.erb的partial里变量名还是ad
6 object和as合用
Ruby代码
<%= render :partial => "contract", :object => @contract, :as => :contract %> <%= render :partial => "contract" %>
7 collection
Ruby代码
<%= render :partial => "ad", :collection => @advertisements %>
@advertisements是一个array，partial里_ad.erb有个ad变量是@advertisements的成员。就是_ad.erb不用写loop只是一条广告显示。
Ruby代码
<%= render :partial => "ad", :collection => @advertisements, :spacer_template => "ad_divider" %>
同上，循环显示_ad.erb _ad_divider.erb 显示@advertisements.size次其中partial_ad_counter是默认计数器表示第几条广告
8 默认
看你要partial的变量是一组记录还是一条记录，会对应约定用locals和collection
Ruby代码
#@account是一条记录
# <%= render :partial => "accounts/account", :locals => { :account => @account} %>
<%= render :partial => @account %>
# @posts是一组记录
# <%= render :partial => "posts/post", :collection => @posts %>
<%= render :partial => @posts %>
这是很人性的约定，可有时候就是忘了
9 一些漂亮的简写
Ruby代码
#<%= render :partial => "account" %>可用下面代替
<%= render "account" %>
#<%= render :partial => "account", :locals => { :account => @buyer } %>可用下面代替
<%= render "account", :account => @buyer %>
# @account是一条记录
# <%= render :partial => "accounts/account", :locals => { :account => @account } %>可用下面代替
<%= render(@account) %>
# @posts是一组记录
# <%= render :partial => "posts/post", :collection => @posts %>可用下面代替
<%= render(@posts) %>
10 layout
Ruby代码
<%# app/views/users/index.html.erb &>
Here's the administrator:
<%= render :partial => "user", :layout => "administrator", :locals => { :user => administrator } %>
Here's the editor:
<%= render :partial => "user", :layout => "editor", :locals => { :user => editor } %>
<%# app/views/users/_user.html.erb &>
Name: <%= user.name %>
<%# app/views/users/_administrator.html.erb &>
Budget: $<%= user.budget %>
<%= yield %>
<%# app/views/users/_editor.html.erb &>
Deadline: <%= user.deadline %>
<%= yield %>
