简单实现js轮播图效果

本文实例为大家分享了js实现轮播图效果展示的具体代码，供大家参考，具体内容如下

html结构

rush:xhtml;"> <Meta charset="UTF-8"> Document

rush:js;"> (function(){ var banner = document.getElementById('banner'); var bannerInner = utils.firstChild(banner); var bannerTip = utils.children(banner,'ul')[0]; var imgList = bannerInner.getElementsByTagName('img'); var oLis = bannerTip.getElementsByTagName('li'); var bannerLeft = utils.children(banner,'a')[0]; var bannerRight = utils.children(banner,'a')[1]; //实现数据绑定：Ajax请求数据、按照字符串拼接的方式绑定数据 var jsonData = null,count = null ~function(){ var xhr = new XMLHttlRequest; xhr.open('get',"json/banner.txt?_="+Math.random(),false); xhr.onreadystatechange = function(){ if(xhr.readyState === 4 && /^2\d{2}$/.test(xhr.status)){ jsonData = utils.formatJSON(xhr.responseText); } } xhr.send(null); }()

~function(){
//绑定轮播图区域的数据
var str = "";
if(jsonData){
for(var i = 0,len = jsonData.length;i<len;i++){
str+='

'
}
//为了实现无缝滚动，需要把第一张克隆一份放在末尾
str+= '

'
}
bannerInner.innerHTML = str;
count = jsonData.length+1;
utils.css(bannerInner,"width",count*1000);
//绑定焦点区域的数据
str = '';
if(jsonData){
for(var i = 0,len = jsonData.length;i<len;i++){
i===0?str+='<li class="bg">':str+='

}
}
bannerTip.innerHTML = str;

}()
//图片延迟加载
function lazyImg(){
for(var i = 0,len = imgList.length;i<len;i++){
~function(i){//这里使用闭包，来避免onload事件异步导致的只有最后一张图片延迟加载的问题
var curImg = imgList[i];
var oImg = new Image;
oImg.src = curImg.getAttribute('trueImg');
oImg.onload = function(){
curImg.src = this.src;
curImg.style.display = "block";
oImg = null;
myAnimate(curImg,{opacity:1},300)
}
}(i)
}
}
window.setTimeout(lazyImg,500);
var step = 0;//记录的是步长，（当前是哪一张图片，0是第一张图片）
//实现自动轮播
var autoTimer = window.setInterval(autoMove,2000);
function autoMove(){
if(step===count-1){
step =0;
bannerInner.style.left = 0
}
step++;
myAnimate(bannerInner,{left:-step*1000},500)
changeTip();
}

//实现焦点对齐
function changeTip(){
var tempStep = step > oLis.length-1 ? 0 : step;
for(var i = 0,len = oLis.length;i<len;i++){
var curLi = oLis[i];
i === tempStep ? utils.addClass(curLi,"bg") : utils.removeClass(curLi,"bg")
}
}
//鼠标滑过停止和开启轮播
banner.onmouSEOver = function(){
window.clearInterval(autoTimer);
bannerLeft.style.display = bannerRight.style.display = 'block';
}
banner.onmouSEOut = function(){
autoTimer = window.setInterval(autoTimer,2000);
bannerLeft.style.display = bannerRight.style.display = 'none';
}
//点击焦点实现轮播图的切换
~function(){
for(var i = 0,len = oLis.length;i<len;i++){
var curLi = oLis[i];
curLi.index = i;
curLi.onclick = function(){
step = this.index;
changeTip();
myAnimate(bannerInner,500)
}
}
}()

//实现左右切换
bannerRight.onclick = autoMove();
bannerLeft.onclick = function(){
if(step<=0){
step = count-1;
utils.css(bannerInner,"left",-steP*1000);
}
step--;
autoMove();
}
})()

绑定的数据

rush:xhtml;"> [ {"img":"img/banner1.jpg","desc":"第一张轮播图"},{"img":"img/banner2.jpg","desc":"第二张轮播图"},{"img":"img/banner3.jpg","desc":"第三张轮播图"},{"img":"img/banner4.jpg","desc":"第四张轮播图"} ]

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持编程之家。

js 轮播图