jquery实现的获取验证码

1.html代码
<input type="text" name="code" id="code" placeholder="请输入验证码"/>
<input type="button" id="btncode" onclick="getcode();" value="获取手机验证码"/>
2.javaScript代码

var count=60;
    var countdown;
    function getcode(){
        var phone = $("#phone").val();
        count = 60;//设置
        countdown = setInterval(CountDown, 1000);
        $.post('user-getcode.html',{phone:phone},function(result){
            if(result['status']==1){
                $("#code").val(result['msg']);
            }
        },'json');

    }
    function CountDown() {
        $("#btncode").attr("disabled", true);//让按钮不可点击
        $("#btncode").val("还剩" + count + " s");
        if (count == 0) {
            $("#btncode").removeAttr("disabled");
            $("#btncode").val("重新发送验证码");
            clearInterval(countdown);
        }
        count--;
    }