When an option is selected that wasn't previously, the onChange
handler can detect this. 如何检测预选选项(即,选择字段是否选择了任何选项)?没有jQuery这可能吗?此事件是否有处理程序,例如onSelected
(与onSelect
突出显示的文本不同)?
例子:
<select onSelected="FunctionRunIfOptionSelected()">
<option> ... </option>
...
</select>
预选选项将在页面加载时被选中。即,动态呈现 HTML:
<option selected> ... </option>