layer.msg弹窗倒计时

//layer.msg弹窗倒计时
//second : 倒计时时间，单位，秒
//content: 弹窗内容，类型；String
function countDown(second,content){
    layer.msg(content, {
        time : 5000,
        shade: 0.6,
        success: function(layero,index){
            var msg = layero.text();
            var i = second;
            var timer = null;
            var fn = function() {
            layero.find(".layui-layer-content").text(msg+' '+i+' ');
            if(!i) {
                layer.close(index);
                clearInterval(timer);
            } 
            i--;
            };
            timer = setInterval(fn, 1000);
            fn();
        },
            }, function() {
            $("#btnSave").removeAttr("disabled");
    });
}