Ruby-on-rails 如何在 Rails 下拉菜单中设置默认选定项？
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How do I set the default selected item in a Rails drop-down menu?
提问by keybored
When creating a standard Rails dropdown menu how do you set which item in the list should be default?
I ask because in the past I've been just putting a nil entry as the first item in my list of values that are going into the drop-down, but when using {:include_blank => true} the blank entry is not the default selected item, the first item from the list is.
创建标准 Rails 下拉菜单时，如何设置列表中的哪个项目是默认的？
我问是因为过去我只是将一个 nil 条目作为进入下拉列表的值列表中的第一项，但是当使用 {:include_blank => true} 时，空白条目不是默认值选定的项目，列表中的第一个项目是。
回答by fl00r
You can use :selected
您可以使用 :selected
<%= f.select :title, ['1','2','3','4'], :selected => '3' %>
回答by Mirko
You have many options to populate <select>tag with <option>tags, one of them is options_for_select(container, selected = nil) which takes a selected param which should be the value of your <option>field you want to be selected by default.
您有许多选项可以<select>用<option>标签填充标签，其中之一是options_for_select(container, selected = nil)它采用选定的参数，该参数应该是<option>您希望默认选择的字段的值。
