js格式化显示当前时间

<script type="text/javascript">
//    function settime() {
//        var mytime = document.getElementByIdx_x_x("mytime");
//        var time = new Date();
//        var text = time.toString();
//        mytime.innerHTML = text;
//       // alert(time);
//    }
//    setInterval(settime, 1000);
  //  settime();

    function showTime() {
        var temp = "";
        var week = new Array("星期天", "星期一", "星期二", "星期三", "星期四", "星期五", "星期六")//0代表星期天，1代表星期一
        var timeNow = new Date();
        var h = timeNow.getHours();
        var s = timeNow.getSeconds();
        var m = timeNow.getMinutes();
        var year = timeNow.getYear();
        var month = timeNow.getMonth() + 1;              //返回0-11
        var i = timeNow.getDay()
        var xingqi = week[i];
        var day = timeNow.getDate();               //返回1-31
        if (h < 10) h = "0" + h;
        if (m < 10) m = "0" + m;
        if (s < 10) s = "0" + s;
        temp = "现在是：" + year + "年" + month + "月" + day + "日 " + xingqi + " " + h + ":" + m + ":" + s;
        mytime.innerHTML = temp; //mytime为页面元素的一个id号
        //var t=setTimeout("showTime()",1000);
    }
    setInterval(showTime, 1000);
</script>

<span id="mytime"></span>