<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>轮播图</title>
<style type="text/css">
*{ margin: 0; padding: 0; text-decoration: none;}
body{padding: 20px;}
#container{ 600px;height: 400px;border: 3px solid #333;position: relative;overflow: hidden;margin: 0 auto;}
#list { 4200px; height: 400px; position: absolute; z-index: 1;}
#list img { float: left;}
#buttons { position: absolute; height: 10px; 100px; z-index: 2; bottom: 20px; left: 250px;}
#buttons span { 10px;height: 10px;border: 1px solid #fff;border-radius: 50%;margin-right: 5px;float: left;background: #333; }
#buttons .on { background: orangered;}
.arrow { cursor: pointer;display: none; line-height: 39px; text-align: center; font-size: 36px; font-weight: bold; 40px; height: 40px; position: absolute; z-index: 2; top: 180px; background-color: RGBA(0,0,0,.3); color: #fff;}
.arrow:hover { background-color: RGBA(0,0,0,.7);}
#container:hover .arrow { display: block;}
#prev { left: 20px;}
#next { right: 20px;}
</style>
</head>
<body>
<div id="container">
<div id="list" style="left: -600px;">
<img src="img/5.jpg" alt="1"/>
<img src="img/1.jpg" alt="1"/>
<img src="img/2.jpg" alt="2"/>
<img src="img/3.jpg" alt="3"/>
<img src="img/4.jpg" alt="4"/>
<img src="img/5.jpg" alt="5"/>
<img src="img/1.jpg" alt="5"/>
</div>
<div id="buttons">
<span index="1" class="on"></span>
<span index="2"></span>
<span index="3"></span>
<span index="4"></span>
<span index="5"></span>
</div>
<a href="javascript:;" id="prev" class="arrow"><</a>
<a href="javascript:;" id="next" class="arrow">></a>
</div>
<script type="text/javascript">
window.onload = function(){
var getById = function(id){
return document.getElementById(id);
}
var container = getById("container");
var list = getById("list");
var btns = getById("buttons").getElementsByTagName("span");
var prev = getById("prev");
var next = getById("next");
var index = 1;
var animated = false;
var timer;
function showBtn() {
//去掉多余的类
for(var i=0;i<btns.length;i++) {
if(btns[i].className == "on"){
btns[i].className = "";
}
}
btns[index - 1].className = "on";
}
//改变list的显示
function animate(offset){
animated = true;
var newLeft = parseInt(list.style.left) + offset;
var time = 300; //位移总时间
var interval = 10; //位移间隔时间
var speed = offset/(time/interval); //每次的位移量
function go(){
if((speed<0 && parseInt(list.style.left) > newLeft) || (speed>0 &&parseInt(list.style.left) < newLeft)){
list.style.left = parseInt(list.style.left) + speed + "px";
setTimeout(go,interval); //函数的递归
}else{
animated = false;
list.style.left = newLeft + "px";
if(newLeft > -600) {
list.style.left = -3000 + "px";
}
if(newLeft < -3000){
list.style.left = -600 + "px";
}
}
}
go();
}
//自动切换
function aotuPlay(){
timer = setInterval(function(){
next.onclick();
}, 3000)
}
function stop(){
clearInterval(timer);
}
//左右按钮添加事件
next.onclick = function(){
if(index == 5){
index = 1;
}else{
index += 1;
}
showBtn();
if(!animated){
animate(-600);
}
}
prev.onclick = function(){
if(index == 1){
index = 5;
}else{
index -= 1;
}
showBtn();
if(!animated){
animate(600);
}
}
//圆点添加事件
for(var i=0;i<btns.length;i++){
btns[i].onclick = function(){
if(this.className == "on"){
return;
}
var myIndex = parseInt(this.getAttribute("index"));
var offset = -600 * (myIndex - index);
if(!animated){
animate(offset);
}
index = myIndex;
showBtn();
}
}
//添加自动播放
container.onmouseover = stop;
container.onmouseout = aotuPlay;
aotuPlay();
}
</script>
</body>
</html>