var t = null;
        t = setTimeout(time,0);
        function time() {
            clearTimeout(t);
            dt = new Date();
            var y = dt.getFullYear();
            var mt = dt.getMonth()+1;
            var day = dt.getDate();
            var h = dt.getHours();
            var m = dt.getMinutes();
            var s = dt.getSeconds();
            document.getElementById('showTime').innerHTML = y+'年'+mt+'月'+day+'日'+h+'时'+m+'分'+s+'秒';
            t=setTimeout(time,1000);
        }