<input type="text" name='' id="btn">
//发送验证码倒计时
var wait=30;
function time(o) {
if (wait == 0) {
o.removeAttribute("disabled");
o.value="免费获取验证码";
wait = 30;
}else{
o.setAttribute("disabled", true);
o.value="重新发送(" + wait + ")";
wait--;
setTimeout(function() {time(o) },1000)
}
}
document.getElementById("btn").onclick=function(){time(this);}
//调用倒计时JS
jq 写法：
<!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>
<script src="HTML/js/jquery-1.4.1.min.js" type="text/javascript"></script>
<script type="text/javascript">
var InterValObj; //timer变量，控制时间
var count = 5; //间隔函数，1秒执行
var curCount;//当前剩余秒数
function sendMessage() {
curCount = count;
//设置button效果，开始计时
$("#btnSendCode").attr("disabled", "true");
$("#btnSendCode").val("请在" + curCount + "秒内输入验证码");
InterValObj = window.setInterval(SetRemainTime, 1000); //启动计时器，1秒执行一次
//向后台发送处理数据
$.ajax({
type: "POST", //用POST方式传输
dataType: "text", //数据格式:JSON
url: 'Login.ashx', //目标地址
data: "dealType=" + dealType +"&uid=" + uid + "&code=" + code,
error: function (XMLHttpRequest, textStatus, errorThrown) { },
success: function (msg){ }
});
}
//timer处理函数
function SetRemainTime() {
if (curCount == 0) {
window.clearInterval(InterValObj);//停止计时器
$("#btnSendCode").removeAttr("disabled");//启用按钮
$("#btnSendCode").val("重新发送验证码");
}
else {
curCount--;
$("#btnSendCode").val("请在" + curCount + "秒内输入验证码");
}
}
</script>
</head>
<body>
<input id="btnSendCode" type="button" value="发送验证码" onclick="sendMessage()" /></p>
</body>
</html>