如何为表单内的选择字段设置默认值

2 ruby-on-rails ruby-on-rails-4

在代码我有:

<%= form_for(:category,:url=>{:action=>'update',:id=>@category.id}) do |f|%>
  <div class="field">
    <b style="color: #808080;"> Cuisine name:&nbsp;</b>
    <%= f.select :cuisine_id,options_from_collection_for_select(@cuisines,"id","cuisine_name"),prompt:'select cuisine'  %>
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我正在使用此表单来更新"cuisine_name".问题是我想为这个字段设置默认值.现在我得到所有值.

dax*_*dax 5

你快到了.来自文档:

options_from_collection_for_select(collection, value_method, text_method, selected = nil)
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所以你需要传递一个参数来创建一个默认选中的选项

options_from_collection_for_select(@cuisines,"id","cuisine_name", <your thing here>)
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