点击按钮60秒倒计时js代码:

<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>