js 写一个简单的时间计时器 

<body onload="startTime()">
<div id="txt" ></div>
<script>
    function startTime(){
        var today = new Date();
        var h = today.getHours();
        var m = today.getMinutes();
        var s = today.getSeconds();
        m = checkTime(m);
        s = checkTime(s);
        document.getElementById('txt').innerHTML=h+":"+m+":"+s;
        setInterval(function(){
            startTime()
        },1000)
    }
    function checkTime(i){
        if(i<10){
            i = "0"+i;
        }
        return i
    }
</script>
</body>
posted @ 2018-08-28 18:28  lieaiwen  阅读(13283)  评论(0)  编辑  收藏  举报