<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>无标题文档</title> <script type="text/javascript" src="js/jquery.js"></script> </head> <body> <input type="button" id="btn" value="免费获取验证码" onclick="settime(this)" /> <script type="text/javascript"> var countdown=60; function settime(val) { if (countdown == 0) { val.removeAttribute("disabled"); val.value="免费获取验证码"; countdown = 60; } else { val.setAttribute("disabled", true); val.value="重新发送(" + countdown + ")"; countdown--; } setTimeout(function() { settime(val) },1000) } </script> </body> </html>