W3School TIY
编辑您的代码：
<html> <head> <script type="text/javascript" src="../jquery/jquery.js"></script> <script type="text/javascript"> i=0; $(document).ready(function(){ $("input").keypress(function(){ $("span").text(i+=1); }); }); </script> </head> <body> Enter your name: <input type="text" /> <p>Keypresses:<span>0</span></p> </body> </html>
查看结果: