fmpq.com
源代码：
点击运行
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>Fmpq教程(fmpq.com)</title> <script src="https://apps.bdimg.com/libs/jquery/2.1.4/jquery.min.js"> </script> <script> $(document).ready(function(){ $(":selected").css("background-color","red"); }); </script> </head> <body> <form action=""> 用户名: <input type="text" name="user"><br> 汽车品牌: <select> <option>Volvo</option> <option selected="selected">Saab</option> <option>Mercedes</option> <option>Audi</option> </select> </form> </body> </html>
运行结果