<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<script type="text/javascript" src="jquery.js"></script>//需要自己引入jquery库
</head>
<body>
<input type="button" id="btn" value="免费获取验证码" onclick="settime(this)" />
</body>
<script>
var countdown = 60;
function settime(obj) {
if(countdown == 0) {
obj.removeAttribute("disabled");
obj.value = "免费获取验证码";
countdown = 60;
return;
} else {
obj.setAttribute("disabled", true);
obj.value = "重新发送(" + countdown + ")";
countdown--;
}
setTimeout(function() {
settime(obj)
}, 1000)
}
</script>
</html>