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"><</a> <a href="javascript:;" id="next" class="arrow">></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();
}
