点击按钮实现倒计时效果

<input type="button" class="code-btn" id="sendSns" value="发送验证码">

.btn-dis, .btn-dis:hover {
background-color: #999;
color: #fff;
cursor: not-allowed;
}

<script src="http://apps.bdimg.com/libs/jquery/1.8.3/jquery.min.js" charset="utf-8"></script>
<script type="text/javascript">
$('#sendSns').click(function(){
timeOut('#sendSns',60);
});
//60秒之后重新发送
function timeOut(id,times){
var sendBtn = $(id);
var html = times+'秒后重新发送';
sendBtn.addClass('btn-dis');
sendBtn.val(html);
sendBtn.attr('disabled',true);

var timer = setInterval(function(){
times--;
sendBtn.val(times+'秒后重新发送');
if(times===0){
clearInterval(timer);
sendBtn.val('发送验证码');
sendBtn.removeClass('btn-dis');
sendBtn.attr('disabled',false);
return true;
}else{
return false;
}
},1000);
}
</script>