51help TIY
码：
<html> <head> <script type="text/javascript" src="../jquery/jquery.js" tppabs="http://www.51help.tk/jquery/jquery.js"></script> <script type="text/javascript"> $(document).ready(function(){ $(".btn1").click(function(){ $("span").text($("p").width()); }); }); </script> </head> <body> <p>度是 <span>unknown</span> px。</p> <button class="btn1">获得宽度</button> </body> </html>
查看结果: