fmpq.com
源代码：
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<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>Fmpq教程(fmpq.com)</title> </head> <body> <h3>访问 OPTGROUP 元素</h3> <select size="4"> <optgroup id="myOptgroup" label="Swedish Cars"> <option value="volvo">Volvo</option> <option value="saab">Saab</option> <option value="koenigsegg">Koenigsegg</option> </optgroup> </select> <p>点击按钮获取选项组的标签/描述。</p> <p id="demo"></p> <button onclick="myFunction()">尝试一下</button> <script> function myFunction(){ var x = document.getElementById("myOptgroup").label; document.getElementById("demo").innerHTML = x; } </script> </body> </html>
运行结果