我做了个随机播放，然后要做循坏遍历异步返回的歌曲数据时候，本来是要做的效果是点击左右按钮可以播放上一首和下一首，但是结果是点击左边按钮直接播放第一首，而点击右按钮的时候直接就播放了最后一首，谁帮忙给个解决思路，代码如下

body{

background:deepskyblue;

}

.container{

margin-top:150px;

}

a{

color: #000;

}

span{

font-size: 2.5em;

}

.music{

border:1px #ddd dashed;

}

.info li{

color: red;

}

.list{

border: 1px dashed #ddd;

}

.time-bar{

width: 0;

height: 5px;

background: yellow;

}

歌单

//加载页面的播放器动画

// setTimeout(function(){

// $('.row').toggle('pulsate');

// console.log('aa');

// },1000);

document.getElementById("audio").setAttribute('loop','loop');//循环歌曲

//异步请求数据库歌曲数据

$(document).ready(function(){

$.getJSON('musicList.php',function(data){

console.log(data);

var playList=data;

doResponse(playList);

})

}

);

//测试数据

// var playList=[{'player':'薛之谦','music':'来日方长'},

// {'player':'薛之谦','music':'一半.mp3'},

// {"player":'邓紫棋','music':'喜欢你.mp3'}];

function doResponse(playList) {

for (var i = 0; i < playList.length; i++) {

$('.list-unstyled.list').append('

' + playList[i].player + playList[i].music + '')

};

var str = $('#audio')[0].getAttribute('src').split('res/');

console.log(str);

$('.info li:first-child')[0].innerHTML = str[1].split('.mp3')[0].split('.');

$('.music ul li a').click(function (e) {

e.preventDefault();

var index = $(this).parent().index();

var x=parseInt(Math.random()*(playList.length-1));

console.log(x);

if (index == 0) {

$('audio').attr('src', 'res/' + playList[x].music);

$('.info li:first-child')[0].innerHTML = playList[x].player;

$('.info li:last-child')[0].innerHTML = playList[x].music.split('.mp3')[0].split('.');

console.log(index);

console.log(i);

} else if (index == 1) {

if ($('#audio')[0].paused) {

$('#audio')[0].play();

$('.control li a span:eq(1)')[0].className = 'glyphicon glyphicon-play'

} else {

$('#audio')[0].pause();

$('.control li a span:eq(1)')[0].className = 'glyphicon glyphicon-stop'

}

//console.log(index);

} else if(index==2) {

$('audio').attr('src', 'res/' + playList[x].music);

$('.info li:first-child')[0].innerHTML = playList[x].player;

$('.info li:last-child')[0].innerHTML = playList[x].music.split('.mp3')[0].split('.');

console.log(index);

}

//console.log(parseFloat($('#audio')[0].duration))

});

}