原生js轮播图

html和css代码

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>轮播图</title>
<script src="a.js"></script>

</head>
<style type="text/css">
*{ 
margin: 0;
padding: 0;
text-decoration: none;
}
#container {
width: 1500px;
height: 600px;
overflow: hidden;
position: relative;
}
#list { 
width: 10500px;
height: 600px;
position: absolute;
z-index: 1;
}
#list img {
float: left;
width: 1500px;
height: 600px;
}
#buttons { 
position: absolute;
height: 10px;
width: 100px;
z-index: 2;
bottom: 20px;
left: 700px;
}
#buttons span {
cursor: pointer;
float: left; 
border: 1px solid #fff;
width: 10px;
height: 10px;
border-radius: 50%; 
background: #333;
margin-right: 5px;
}
#buttons .on { 
background: orangered;
}
.arrow { 
cursor: pointer;
display: none;
line-height: 39px;
text-align: center;
font-size: 36px;
font-weight: bold;
width: 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>
<body>
<div id="container">
<div id="list" style="left: -1500px;">
<img src="5.jpg" alt="1"/>
<img src="1.jpg" alt="1"/>
<img src="2.jpg" alt="2"/>
<img src="3.jpg" alt="3"/>
<img src="4.jpg" alt="4"/>
<img src="5.jpg" alt="5"/>
<img src="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">&lt;</a>
<a href="javascript:;" id="next" class="arrow">&gt;</a>
</div>
</body>
</html>

 

 

js代码

window.onload = function () {
var container = document.getElementById('container');
var list = document.getElementById('list');
var buttons = document.getElementById('buttons').getElementsByTagName('span');
var prev = document.getElementById('prev');
var next = document.getElementById('next');
var index = 1;
var len = 5;
var animated = false;
var interval = 3000;
var timer;


function animate (offset) {
if (offset == 0) {
return;
}
animated = true;
var time = 300;
var inteval = 10;
var speed = offset/(time/inteval);
var left = parseInt(list.style.left) + offset;

var go = function (){
if ( (speed > 0 && parseInt(list.style.left) < left) || (speed < 0 && parseInt(list.style.left) > left)) {
list.style.left = parseInt(list.style.left) + speed + 'px';
setTimeout(go, inteval);
}
else {
list.style.left = left + 'px';
if(left>-500){
list.style.left = -1500 * len + 'px';
}
if(left<(-1500 * len)) {
list.style.left = '-1500px';
}
animated = false;
}
}
go();
}

function showButton() {
for (var i = 0; i < buttons.length ; i++) {
if( buttons[i].className == 'on'){
buttons[i].className = '';
break;
}
}
buttons[index - 1].className = 'on';
}

function play() {
timer = setTimeout(function () {
next.onclick();
play();
}, interval);
}
function stop() {
clearTimeout(timer);
}

next.onclick = function () {
if (animated) {
return;
}
if (index == 5) {
index = 1;
}
else {
index += 1;
}
animate(-1500);
showButton();
}
prev.onclick = function () {
if (animated) {
return;
}
if (index == 1) {
index = 5;
}
else {
index -= 1;
}
animate(1500);
showButton();
}

for (var i = 0; i < buttons.length; i++) {
buttons[i].onclick = function () {
if (animated) {
return;
}
if(this.className == 'on') {
return;
}
var myIndex = parseInt(this.getAttribute('index'));
var offset = -1500 * (myIndex - index);

animate(offset);
index = myIndex;
showButton();
}
}

container.onmouseover = stop;
container.onmouseout = play;

play();

}

　　

posted @ 2018-01-26 10:49  从前有一个香蕉  Views(198)  Comments(0)    收藏  举报