html5 效果按下鼠标数值自动增长

<!doctype html>

<html>

<head>

<style>

* {

    margin:0;

    padding:0;

}

div {

    margin:10px auto;

    width:300px;

    text-align:center;

}

meter {

    border:1px solid red;

    width:300px;

}

</style>

</head>

<body>

<div>

  <meter id="song" min="0" max="100" high="70" value="10"></meter>

  <button id="add">增加</button>

  <button id="minus">减少</button>

  <div id="num">10</div>

</div>

<script>

function $(id)

{

    return document.getElementById(id);

}

$('add').onclick = function(){

    var val = $('song').value;

    val ++;

    $('song').value = val;

    $('num').innerHTML = val;

}

var timer = null;

var start_timer = null;

$('add').onmousedown = function(){

    //延迟两秒

    start_timer = setTimeout(function(){

        timer = setInterval(function(){

            var val = $('song').value;

            val += 1;

            $('song').value = val;

            $('num').innerHTML = val;

        },150)

    },500)

}

$('add').onmouseup = function(){

    //清除启动器

    clearTimeout(start_timer);

    //清除间隔启动器

    clearInterval(timer);

}

</script>

</body>

</html>

效果图：

　　 html5 效果按下鼠标数值自动增长

html5 效果 按下鼠标数值自动增长

html5 效果按下鼠标数值自动增长