html5结合javascript实现简易音乐播放器

<div id="music">
	<div id="container">
		<h3 id="musicName">一月，银装轻舞-紫竹笛韵</h3>
		@@##@@
		<audio src="./music/一月，银装轻舞-紫竹笛韵.mp3" controls id="audio"></audio>
		<div class="btn">
			<button id="play">play</button>
			<button id="pause">pause</button>
			<button id="prev">prev</button>
			<button id="next">next</button>
		</div>
	</div>
</div>

// 播放
play.onclick = function(){
	if(audio.paused){
		audio.play();
	}
}
 
// 暂停
pause.onclick = function(){
	if(audio.played){
		audio.pause();
	}
}

audio.addEventListener('ended',function(){
	next.onclick();
},false);

// 上一首
prev.onclick = function(){
	num = (num + len - 1) % len;
	audio.src = './music/' + music[num] + '.mp3';
	musicName.innerHTML = music[num];
	bgImage.style.backgroundImage = 'url(./image/' + music[num] + '.jpg)';
	musicImg.src = './image/' + music[num] + '.jpg';
	audio.play();
}
 
// 下一首
next.onclick = function(){
	num = (num + 1) % len;
	audio.src = './music/' + music[num] + '.mp3';
	musicName.innerHTML = music[num];
	bgImage.style.backgroundImage = 'url(./image/' + music[num] + '.jpg)';
	musicImg.src = './image/' + music[num] + '.jpg';
	audio.play();
}

#music {
	width: 500px;
	height: 500px;
	border-radius: 10px;
	margin: 20px auto;
	position: relative;
	background: url(./image/一月，银装轻舞-紫竹笛韵.jpg) no-repeat;
	background-size: cover;
	text-align: center;
}
#container {
	position: absolute;
	left: 0;
	right: 0;
	top: 0;
	bottom: 0;
	width: 500px;
	height: 500px;
	text-align: center;
	background:rgba(255,255,255,0.6);
}