spring 向表单添加默认值：选择
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spring add default value to form:select
提问by Mike
I'm developing a spring application, now I've added a dropdownlist to one of my jsp pages using:
我正在开发一个 spring 应用程序，现在我使用以下命令向我的一个 jsp 页面添加了一个下拉列表：
<form:select multiple="single" path="users[y.count-1].X" items="${Y}" itemValue="id" itemLabel="name"/>
Now I'd like to add the default value "Nothing selected", however I can't seem to find how to do this. I've tried:
现在我想添加默认值“未选择任何内容”，但是我似乎无法找到如何执行此操作。我试过了：
<form:select multiple="single" path="users[y.count-1].X" items="${Y}" itemValue="id" itemLabel="name">
<form:option value="Nothing selected" />
</form:select>
But "Nothing selected" isn't displayed in my dropdownlist.
但是“未选择任何内容”未显示在我的下拉列表中。
回答by Jacob Mattison
You should be able to do
你应该能够做到
<form:select multiple="single" path="users[y.count-1].X" >
<form:option value="Nothing selected" />
<form:options items="${Y}" itemValue="id" itemLabel="name" />
</form:select>
回答by zygimantus
Just add this line before your options:
只需在您的选项之前添加此行：
<form:option selected="true" value="..." />
